Sonos Arc loud pop then audio loss


Userlevel 3

I was playing on my Xbox when the arc suddenly made an extremely loud pop sound and then lost audio completely. The app wouldn’t let me adjust the volume and Alexa wake up didn’t emit its usual tone. I had to remove the power from the arc and reapply which resumed the audio. I’m concerned that one of the speakers in the arc may have been damaged when this happened. Has anyone had this issue?

We have had no issues with the arc since purchasing it earlier this year.

Corry P 3 months ago

Hi Everyone!

Good news! We are pleased to share that our team has identified a fix for the popping sound on Arc and it will be shipped to all customers as part of a software release today, Thursday Nov 16 at 09:30 ET, 14:30 GMT, 15:30 CET. Please note that some app stores may take an extra hour or two for it to become available.

During our investigation we uncovered a rare bug that impacts how Sonos Arc and Beam (Gen 2) in certain home theater configurations process Dolby MAT, a streaming technology which is used to deliver Dolby Atmos audio over HDMI. Occasionally a Sonos product will receive a corrupted audio segment from an external source and needs to filter out unwanted audio data. The bug we identified was allowing our Dolby decoder to play audible errors on certain home theater setups rather than concealing them. The solution we’ve built and tested improves our Dolby decoder so it better filters out corrupt audio data that can manifest as a popping sound. We’ll continue to monitor customer feedback closely after the fix has been released and ship additional updates if necessary.

We strive to deliver the best listening experience possible and work to address major issues that impact our customers. We apologize for the disruption this bug has caused and want to thank you for your patience while our team developed a fix.

We would also like to thank our community users for their detailed setup information and steps to reproduce the issue, which were helpful to us in uncovering the cause of the bug.

 

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Userlevel 4
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So, I’m going to take a shot at summarizing my take on the issue after extensive reading and building on the excellent troubleshooting work by others in this thread.

The Xbox One X/S and ATV 4K use a Dolby MAT 2.0 encoder (metadata-enhanced audio transmission) to output sound – this process takes Dolby Digital Plus (DD+) or Dolby True HD Atmos bitstream and repackages it as LPCM output (linear pulse code modulation) with attached Dolby Atmos metadata. Think of it as LPCM with attached Atmos data. This Dolby MAT output is sent via HDMI to a receiver or soundbar that has a built-in decoder (in this case, the Sonos Arc and Beam). Per Dolby, the final device in the pass-through chain must have a decoder capable of processing the Dolby MAT format. As described by AV Pro Edge:

Within the MAT encode process, the bitstreams are encoded into encapsulated MAT frames, converted to LPCM and ferried over HDMI 1.3 or later using a fixed bit-rate, into a compatible AVR/processor with a Dolby MAT decoder that unpacks and converts the MAT frames into the original Dolby bitstreams. Apple TV as of tvOS 16.2 does NOT support pass-through bit streams. Atmos is sent as Dolby Metadata-enhanced Audio Transmission (Dolby MAT) via LPCM. If Dolby Atmos is off the E-AC-3 audio is sent without metadata.


This is why you will typically see LPCM (or “Dolby Atmos”) as the output type in the Sonos app when streaming Atmos content via Apple TV or Xbox – by definition, Dolby MAT 2.0 involves conversion into LPCM + Atmos metadata by the encoding device. As Dolby itself details:

With the introduction of Dolby Atmos, we have expanded the Dolby MAT technology to support encoding and decoding of Dolby Atmos metadata incorporated in lossless pulse-code modulation (PCM) audio. A key benefit of Dolby MAT 2.0 is that Dolby Atmos object-based audio can be dynamically encoded in real time and transmitted from a source device with limited latency and processing complexity. Likely sources that will employ Dolby MAT encoding include broadcast set-top boxes and game consoles. The Dolby MAT 2.0 decoder outputs the object-based audio and its metadata for further processing inside the device.


Sonos explicitly advertises support for this format; their various descriptions of the audio formats are a little muddled, to be honest, with some redundancy in terminology. But they clearly outline support for Dolby Atmos in the form of Dolby Multichannel PCM with Atmos object data delivered via MAT. This is the exact format used by Xbox and Apple TV. You can see a detailed discussion of this here by a staff member that explained these nuances when the Arc was initially released: “Arc-compatible codecs that contain Dolby Atmos include Dolby Digital Plus, Dolby TrueHD, and Dolby MAT.” I think there are a few minor errors in this explanation in that Dolby MAT isn’t exactly a codec per se – rather, as AV Pro Edge explains:

Dolby MAT is neither a codec nor a format. While Dolby MAT utilizes an encode/decode algorithm, it is constrained within a closed environment, devoid a final analog stage. Dolby MAT might be defined as an encode/conversion/transport/conversion/decode process, a “bridge” created between compatible Dolby MAT devices for any of the three codecs Dolby has designated to deliver Dolby Atmos content to the home, Dolby Digital Plus/JOC, Dolby TrueHD, and with ATSC 3.0 tuners, Dolby AC-4. Dolby MAT takes advantage of the high-capacity lanes provided by the eight, 16bit, 192kHz audio carrier lanes in the HDMI standard, starting with HDMI 1.3, and aggregates the bandwidth of multiple lanes to establish a data transport layer.


Based on the multitude of comments and complaints both on the Sonos forum and other sites, it seems very clear that the popping, gunshot-esque banging sound, and audio dropouts are almost certainly isolated to Atmos content delivered via Dolby MAT 2.0 encode/decode process. This also explains why these issues are isolated to streaming devices that utilize this format (Xbox and ATV).

I am open to the idea that this could be related to an issue on the encoding side (ie Xbox or Apple TV) of the MAT 2.0 container. However, the fact that devices produced by two different companies (Microsoft and Apple) that encode using the MAT 2.0 format both produce issues with sound delivery on the Arc leads one to believe that this is an issue on the decoding (Sonos) side. If Sonos advertises compatibility with MAT 2.0 Atmos (LPCM + Atmos data), I am curious what output device they used to even test that compatibility in the first place. Given that Xbox and ATV are the main devices using this encoding process, it would seem odd to brand the device as “compatible” without testing the only two known streaming boxes that use the format? Dolby also anticipates more devices will start using MAT over the coming years, as well. Further, Sonos continues to advertise compatibility over three years into a widely known issue. Sonos support recommends turning off Atmos in the ATV to solve the issue – this obviously works (as it has for me) because it removes the aforementioned problems from the equation at the expense of Atmos functionality. Further, there are also numerous examples by people out there with receivers and sound bars that work perfectly fine with streamers that re-encode to an uncompressed multichannel LPCM with Dolby MAT 2.0 stream, which seems to suggest that there are hardware and software differences in the decoding devices (receiver/soundbar) that significantly impact the ability to deliver this content effectively.

As I’ve stated before, we wouldn’t be in a position of speculating if Sonos commented more meaningfully on the problem. Responses over the last THREE YEARS have been non-specific, devoid of technical details, and absent any accountability for moving the issue forward. I was told that this was an “extremely transient, low-probability phenomenon.” I strongly disagree – I think this is simply a reflection of the reality that, more commonly, users of the Arc do not have the required audio set up (ATV/Xbox + top-tier streaming subscription with Atmos content + Atmos-recorded content + TV with eARC and appropriate pass-through) to produce the issue. It doesn’t mean the issue isn’t persistent and affecting thousands of users. In fact, as the volume of Atmos-enabled content on streaming services such as Netflix, Amazon, and Apple TV+ increases and more people upgrade to newer TV sets with eARC and Atmos passthrough compatibility, the issue will likely become even more common. As anyone here who is impacted knows, reproducing it is not challenging – just fire up some Atmos content on the Apple TV and you can expect to hear a gunshot sound followed by audio loss within the first 5-10 minutes. I’m happy to have a Sonos technician come to my house (or send in my equipment) if reproducibility is the concern here – they have not taken me up on this offer. Bottom line, the ideal solution is for Apple/Microsoft to provide an option to bitstream DD+ and TrueHD with Atmos natively via passthrough – but my main complaint with Sonos is advertising compatibility with MAT Atmos delivery and doing little to address the concerns of a loyal (though less so with this behavior) fan base.

If Sonos strongly believes this is an upstream issue with the ATV/Xbox encoding/timing process, it would even be helpful to be presented with technical information to support this. It would allow those affected to take this information to Apple, Microsoft, and Dolby developers to further narrow down the problem. And if this is the case, there should also be a disclaimer that Arc and Beam do not currently support any Dolby MAT 2.0 streaming devices actively on the market. But here we are, three years in, with nearly zero helpful information from the engineering team.

To be honest, I am just really disheartened by the response from the Sonos team. I have been a loyal Sonos user for 7+ years and have spent thousands on Sonos products and recommended them to friends and family. The response has been nothing short of anemic. It’s true that many people with the Arc and Beam 2 are not affected by this issue – unless you are interfacing with Atmos content delivered via MAT, you probably are unlikely to ever experience this problem. But for those of us who are impacted, it is a huge issue. It makes Atmos unusable. I’d feel a heck of a lot better if there had been a meaningful, public response from the company addressing this issue – but here we are. I just don’t feel like I can recommend these products moving forward unless something changes.

I hope some of the recent activity in this thread serves as a call to action. If we do not get a more meaningful response from the company (@Corry P, please help!) over the next month, I aim to pursue other avenues for bringing attention to the issue more publicly and would welcome anyone who would like to contribute. I would like to give Sonos an opportunity to respond first, but I don’t have a lot of optimism based on this thread.  I’ll end by highlighting a few comments in this forum that summarize the frustration.

@Cavecanem  I have contacted in multiple times support via phone and email, with the same corporate response everyone here has experienced.

@mond0  Lurking this forum and reading all these stories of how Sonos support has been deflecting and gaslighting their customers for years has made me reconsider ever purchasing a Sonos product.

@Rios  As I’ve said before this is a Sonos hardware bug that can be recreated with the same parameters 100% of the time. Each time I read how we have to turn off the feature that we specifically paid for is infuriating.

@BobSmithHome  After reading almost all of this 2 year old thread, I’m shocked that Sonos is sending these out to unsuspecting customers with no warning or recommendations. If I had any faith that Sonos was really doing something, I’d keep it and wait for a fix. But it’s pretty clear after reading this thread that they’re just jerking us around. 

@Rowley_1  Beyond a joke, this is a company knowingly selling a product that has issues performing what it’s advertised to do to consumers without warning them. After the whole S1 to S2 forced obsolescence debacle, I should have learnt my lesson.

@Schlagdog I can’t believe after 2 years Sonos still hasn’t fixed this. I was watching an atmos movies and literally 10 seconds into it the loud POP OF DEATH and arc is done...The ARC to me is pretty disappointing to say the least and the lack on someone that actually works at Sonos to have a real answers is embarrassing. 

@blunderdomeYou know this is almost more frustrating to hear than just radio silence.  Two years into this thread and “We’re aware of the issue and are looking into it” simply isn’t good enough.

Userlevel 7
Badge +18

Hi Everyone!

Good news! We are pleased to share that our team has identified a fix for the popping sound on Arc and it will be shipped to all customers as part of a software release today, Thursday Nov 16 at 09:30 ET, 14:30 GMT, 15:30 CET. Please note that some app stores may take an extra hour or two for it to become available.

During our investigation we uncovered a rare bug that impacts how Sonos Arc and Beam (Gen 2) in certain home theater configurations process Dolby MAT, a streaming technology which is used to deliver Dolby Atmos audio over HDMI. Occasionally a Sonos product will receive a corrupted audio segment from an external source and needs to filter out unwanted audio data. The bug we identified was allowing our Dolby decoder to play audible errors on certain home theater setups rather than concealing them. The solution we’ve built and tested improves our Dolby decoder so it better filters out corrupt audio data that can manifest as a popping sound. We’ll continue to monitor customer feedback closely after the fix has been released and ship additional updates if necessary.

We strive to deliver the best listening experience possible and work to address major issues that impact our customers. We apologize for the disruption this bug has caused and want to thank you for your patience while our team developed a fix.

We would also like to thank our community users for their detailed setup information and steps to reproduce the issue, which were helpful to us in uncovering the cause of the bug.

 

Userlevel 4
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i wonder what happened with tom warren set, did they fixed it for him, tried to ask him in twitter but he didn't respond 

its shame that sonos don't have anything to say about this issue, no ETA for fix

If I understand it correctly, @tomwarren disabled eARC (thereby dropping from Dolby MAT to DD+ Almos) to avoid the issue. I think his attention shifted to other topics once he was no longer affected.

Or you can hop on the conspiracy crazy-train and speculate that Sonos let Chris Welch etc know that they will lose their preferred access to Sonos execs and upcoming products if they keep on this issue. :)

Don’t worry Sonos haven’t locked us up or bullied us into silence :)

I have good news from Sonos though:

“Our team has identified a possible fix and is quickly working to field test the solution. While we aren’t able to share a specific timeframe for deployment, we can confirm that progress has been made.”

No timeframe just yet, but it’s encouraging that they’ve identified a potential fix now instead of having issues replicating the problem.

Userlevel 2

Hi all,

We've seen the need to remove some posts from this topic as they're breaking the Beta NDA, which we take very seriously. With that said, yes, there is progress on a fix for the Arc popping that some users have experienced, so we kindly ask you to continue to be patient while we’re working to give you a better experience.
We will of course let you know if there is any news around this topic that can be shared.
Thank you for respecting our terms and conditions for participating in both this forum and our Sonos Beta program.

Userlevel 6
Badge +5

A small update and big thank you for the community:

Earlier today I spoke with a Sonos engineer. It was a very positive experience. He was knowledgeable about the problem and had been thinking about it for over a year, including having had an interaction with the CEO about it.

He logged into my computer to access my Arc and put it into devmode. The Arc will leave devmode if rebooted. Then he supplied me with three local URLs to access the devmode functions. The first causes the Arc to save the sound data from the last minute. The second downloads that save file. The third files a diagnostic, same as the app but more convenient.

So far I have submitted three pop files to him. Two files from two different Apple Music songs on Apple TV and one while the Apple TV was on screensaver and not playing any sound. I hope to also generate a file from the Xbox doing it, but I have not had time to get that done.

A big thank you to all of you in the community for contributing your experiences in this thread. If we had only been individually reaching out to support, I am sure we would still be changing cables, factory resetting, etc. The reason I am in a position to have real interactions with Sonos now is because I am standing on your shoulders.

Userlevel 4
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I just started having the issue over the past couple of weeks on my personal system at home and I’m shocked to hear it has been affecting people for years. I’m also a reporter at The Verge, so I’ll do my best to get Sonos to comment on this properly. It’s a disgrace that they haven’t so far.

Userlevel 4
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We have a response, but all it largely says is that they can’t reproduce the issue. I’m going to offer to ship my TV, Sonos Arc, and Xbox to Sonos.

 

https://www.theverge.com/2023/8/10/23824258/sonos-arc-dolby-atmos-problems-loud-audio-pop

Userlevel 4
Badge +2

Hi all,

We've seen the need to remove some posts from this topic as they're breaking the Beta NDA, which we take very seriously. With that said, yes, there is progress on a fix for the Arc popping that some users have experienced, so we kindly ask you to continue to be patient while we’re working to give you a better experience.
We will of course let you know if there is any news around this topic that can be shared.
Thank you for respecting our terms and conditions for participating in both this forum and our Sonos Beta program.

I appreciate the posts might technically break the beta NDA that Sonos enforces on people, but this is an ideal time to be a little more transparent here after years of silence. Folks have been waiting 3 years for a fix on this issue, for hardware they’ve spent thousands of dollars on. The fix isn’t to provide a “better experience” it’s to provide the Dolby Atmos experience that Sonos customers thought they were getting when they purchased a Dolby Atmos soundbar.

Userlevel 4
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Hello all. I would like to take a second to thank @tomwarren for using his platform to bring attention to this issue - it’s long overdue. And to thank others on here who have continued to advocate for a solution. It’s frankly a shame that it has taken this much public pressure and complaining by a loyal customer base (myself included) to even get a public response from Sonos. I was even more dismayed by the generic and noncommittal response by Sonos to the article.

I will also share some information that *could* be helpful in the limited responses I have received from the Sonos technical team. In the diagnostic samples that I have provided, I have been told that the popping sound “doesn't happen when” the collected audio taps in the diagnostic are played back by the Sonos technical team. I don’t know enough about what specific details the diagnostics samples record or what is contained in these “audio taps.” I was also told that there are customers who have multiple Arcs that only have issues with one device, and when devices are swapped, the popping issue does not follow the Arc. I wonder if anyone here can confirm that. The implication would be that the etiology of the pop is an interoperability issue. More than anything, I think this just supports my argument: the pop isn’t following the device because it is being switched to a set-up that is no longer using a Dolby MAT format, thus alleviating this issue. This means that Arc is having issues with Dolby MAT, as I have explained previous.

Support did confirm that all of the pops and cracks “excite the Dolby Atmos (MAT) as the active format...but the decoded output is free of any objectionable artifact like a pop. It's possible that the pop - if it's indeed originating from the pipeline - to have occurred just prior to the MAT feed, in the form of PCM audio (even then, only in some and not all of the cases).” I personally do not see evidence that this is the case, as I have been watching my app data when a pop occurs, and the popping happens after Atmos content has already kicked in and is playing - I do not see any switching back to PCM audio.  

I was also told that “NSD on the TVP is not run on encoded content (we trust these signals to be kosher) and only offers audio Vs silence discrimination with PCM audio. i.e, if the audio signal itself contained an objectionable pop, we don't presently exercise the noise classification as an additional line of defense. The probability of such an event based on the many, many taps & diags, thus far, is evidently very low, though.” I honestly do not know enough to parse out what any of this means. As I have said before, despite my best efforts to self-educate (over many, many hours), I don’t think the end customer should have to be versed in these details - for $900, these devices should work out-of-the-box, and issues that arise should be fixed or advertising promptly changed. This also seems to suggest (as I have advocated previously) that Sonos *could* engineer a way to make these popping sounds FAR LESS damaging (ie gunshot scaring children, pets, and viewers) by enacting an additional line of defense if any of these issues are actually originating upstream (again, skeptical until proven otherwise that this is exclusively an upstream problem).

Of the four most recent diagnostics that I have submitted, I was told that “the taps are all 4 seconds long & barring [one sample] are entirely filled with silence. The sequence of events in these 4 diags are all very different, allowing for no common suspects to be easily revealed by the logs.” 

All of this leads me to wonder how helpful the diagnostics samples are in the first place. I don’t have enough technical-know-how to understand exactly what information is sent to Sonos what a diagnostic sample is submitted. I can’t square the fact that the Sonos support team hears “silence” in the audio tap when I feel like I’m gearing up for a home invasion. This makes me question whether the audio taps are truly providing robust information about the sounds being produced by the device. Honestly, to me, the popping sound is akin to an electrical surge. It’s like someone has shorted the speaker, blown a tweeter, and killed the power. Perhaps this isn’t being captured in the samples.

I share all this because Sonos has not provided much information from a technical side publicly. Perhaps someone more knowledgable than myself can use this to progress this issue. @tomwarren, I would encourage you and anyone else with a louder voice than the rest of us to keep the gas pedal on this issue - Sonos has demonstrated that the issue will die unless we continue to press for a solution. We have seen promised “work on a solution” for three years, always devoid of specifics or a timeline. At a minimum, they could commit to changing their product advertising until a solution is found. This would at least make me feel like they are not okay with continued false advertising and truly being upfront with new customers - until this is done, it’s hard to see any response from Sonos as being in good faith.

I see a number of comments on the articles written this week from potential customers that are now having second thoughts about purchasing an Arc - good, they should, until this issue is resolved. Sonos has demonstrated that they aren’t going to respond to this issue out of a commitment to customers alone - it’s going to have to start hurting sales and the bottom line, unfortunately. I hate that this has how the issue has evolved - I have invested substantively in the Sonos ecosystem and touted to so many family and friends. This used to be a brand that I believed in and supported, despite a premium price point. In order to build a brand for premium audio products, it seems like Business 101 is to provide reliable, meaningful customer service. 

Userlevel 3

So after 2 years this is finally supposedly fixed.  I’m getting ready to update and then play some Atmos music off iTunes. If this thing pops and explodes like it always does I’m going to explode also. This atmos problem with some players is seriously embarrassing that it’s been a 2 years problem reported thousands of time. I will post the results good or bad.  
 

 

I CAN REPORT I HAVE SUCCESSFULLY BEEN ABLE TO LISTEN TO 3 SONGS IN ATMOS WITHOUT THE USUAL EXPLOSION WITHIN 15 SECONDS. 

Userlevel 4
Badge +1

I really don’t quite understand the insistence by @ken_griffiths that this is making a claim that the Arc does not support Atmos is a “non-starter.”

There are three mechanisms for delivering Atmos content, as I understanding it, (1) DD+, (2) Dolby TrueHD, and (3) Dolby MAT. I don’t see any reason to disagree with your assertion that DD+ and Dolby TrueHD formats are performing as expected on the Arc. However, it seems incredibly clear at this point that the Arc is unable to correctly decode/handle Dolby MAT formats - which is used by Apple TV and the XBox. Based on your post history, you have not experienced these issues because you are not using a streaming device that outputs in the Dolby MAT format. That’s great for you - but it doesn't address the ongoing issue that many other Arc owners still face.

And in fact, Sonos staff themselves explains here OVER THREE YEARS AGO that Arc is *supposed* to support all three formats of Dolby Atmos – via DD+, TrueHD, and Dolby MAT. What I think is clear at this point is that the Arc is unable to deliver Atmos content via Dolby MAT format, which is why we are seeing issue with the Apple TV and Xbox, which use those formats. We understand that you haven’t had an issue with your devices - but you can’t really comment on the horrible experience of those using mainstream devices delivering one of other MAIN types of Atmos content delivery. 

You reference the footnote on the home theater audio formats page, but it’s honestly kind of unintelligible to me (and not really clear what it’s trying to say - is it supposed to be a disclaimer?). It mentions Dolby MAT but doesn’t really comment on the implications (if any) of this format - why is it even on this page if there isn’t further clarification regarding why this distinction is even being highlighted?

And to be honest, the lay user of home electronics should not have to spend hours reading about Atmos delivery formats to understand why their device isn’t working. If you are going to advertise the Arc as being Atmos-capable (and talk in your forums about how it supports all Atmos delivery formats and codecs), then it needs to work for people using the device with two of the most common streaming devices that exist. The sound it makes really, truly sounds like a gunshot - it wakes my family from the other side of the house.

As @KrylonBlue stated quite well: 

Sonos released a product that isn’t capable of handling a format of Atmos that is used by two or more of the largest devices on the market. We’re not talking about some off the wall streaming box but rather an Xbox and Apple TV. If Sonos is going to sell an Atmos enabled product they must work as an Atmos enabled product as a whole. 


More importantly, we shouldn’t even BE in the position of wildly speculating about what is causing the issue, because at the end of the day, this is an issue impacting MANY Sonos customers, and it has been largely radio silence from the company regarding what has actually been done to troubleshoot the issue. If someone from Sonos could actually provide specific information about exactly what has been done from an engineering perspective, maybe we wouldn’t have a thread with 870+ responses trying to figure out why this issue persists. What does happen with all those diagnostics we submit, after all? As @blunderdome and others have said:

You know this is almost more frustrating to hear than just radio silence.  Two years into this thread and “We’re aware of the issue and are looking into it” simply isn’t good enough.


We are three years into this issue. It’s well known and documented. Videos have been uploaded. The issue is reproducible easily for those with the affected streaming devices. Removing the TV from the equation with devices such as Arcane also hasn’t solved the issue. Nor has disabling functions such as CEC. It’s not like Sonos is a low-budget brand - people have spent thousands of dollars for their systems, and really, if you are advertising Sonos Atmos compatibility, it should work with one of the most widely used streaming devices in the world. 

Continued apathy towards this issue really isn’t acceptable. I’m at the point where I would favor drafting a letter to the company and welcoming signers. It should get the attention of Ars Technica, Rtings, and other organizations in the tech/audio community - I’m more frustrated now out of principal. It would be one thing if they were more publicly responsive to the issue and demonstrating clear and well-articulated efforts to troubleshoot the issue rather than generic platitudes, but frankly, at this point it’s unacceptable. 

Userlevel 4
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I’m able to reliably reproduce the issue, that’s how I captured it on video. I’ve offered to work with Sonos engineers to troubleshoot, so we’ll see if they’re able to do that remotely or not. 

Userlevel 4
Badge +3

Fantastic job RC12

One additional thing to consider in your write-up, that even though the TV passes through the audio signal, it acting as middle man still needs to do work particularly when changing the audio format.  
 

My personal experience only has popping on the SeriesX when I return to the Home Screen, never during gameplay.  This says to me that the renegotiation of the new audio format has something to do with it.  I am also part of the minority that has seen popping completely relieved when deactivating Dolby Vision as a companion and I’m honestly not sure if that points to CEC, or HDMI bandwidth limitations during renegotiation.  If it helps I have had two TVs which produce the same effect.  One a LG C1 which only has a 40gbps HDMI port and the other was a Sony x900 who has a completely botched 4K/120 implementation due to bandwidth.  I do play on 4K/120 and to be honest I have never tested to see if I get the pop on 4K/60 or 1080p/120 formats.

 

All of this information might not matter, but ive never ruled out the TV being the middle man as a potential source of the problem.  With such a detailed and well researched writeup, it probably deserves at least a snippet as I see it being passed around the internet

 

Again congrats on the write-up.  Probably the best post we have seen on this issue

Userlevel 4
Badge +1

Hey @Corry P would you or one of your colleagues be able to provide some updates on this issue? It would be helpful for those of us (877 replies on this thread is a bad sign) impacted to get some more specific clarity on precisely who is working on this issue and what has been done so far. I know some have raised the point that it is challenging to reproduce - I am more than happy to send a video or send in my unit because its honestly pretty easy to reproduce because it happens so regularly and predictably with Atmos content (LG C2 TV with Apple TV). Where do things stand presently?

Userlevel 4
Badge +2

Hi Everyone!

Good news! We are pleased to share that our team has identified a fix for the popping sound on Arc and it will be shipped to all customers as part of a software release today, Thursday Nov 16 at 09:30 ET, 14:30 GMT, 15:30 CET. Please note that some app stores may take an extra hour or two for it to become available.

During our investigation we uncovered a rare bug that impacts how Sonos Arc and Beam (Gen 2) in certain home theater configurations process Dolby MAT, a streaming technology which is used to deliver Dolby Atmos audio over HDMI. Occasionally a Sonos product will receive a corrupted audio segment from an external source and needs to filter out unwanted audio data. The bug we identified was allowing our Dolby decoder to play audible errors on certain home theater setups rather than concealing them. The solution we’ve built and tested improves our Dolby decoder so it better filters out corrupt audio data that can manifest as a popping sound. We’ll continue to monitor customer feedback closely after the fix has been released and ship additional updates if necessary.

We strive to deliver the best listening experience possible and work to address major issues that impact our customers. We apologize for the disruption this bug has caused and want to thank you for your patience while our team developed a fix.

We would also like to thank our community users for their detailed setup information and steps to reproduce the issue, which were helpful to us in uncovering the cause of the bug.

 

Great news Corry. Thanks to the team for investigating this and getting a fix out. I know it wasn’t an easy problem to identify and work on.

 

Userlevel 6
Badge +5

This thread alone has users affected by the problem on Samsung, Sony, and LG TVs. If this issue appears on the three largest manufactures, as well as both major consoles (with the PS5 Atmos update), and Apple TV; there is nothing limited to it. 

Userlevel 1

I’ve been gaming and playing music for hours straight with Atmos enabled and no pops. Looks good so far! 3080 w/Sony TV. 

Userlevel 4
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Hey guys I have received back an email from Sonos Level 3 support team . It looks like they have more info about the POP and sounded promising . Will keep you guys updated soon once I receive more info from them 

 

Moderator edit: removed case number from picture

Userlevel 6
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We have a response, but all it largely says is that they can’t reproduce the issue. I’m going to offer to ship my TV, Sonos Arc, and Xbox to Sonos.

 

https://www.theverge.com/2023/8/10/23824258/sonos-arc-dolby-atmos-problems-loud-audio-pop

@tomwarren Thank you, Tom. It means so much to us that someone is finally noticing.

I would like to direct you to an interaction I had with Sonos on December 21 of 2022. They had an engineer work directly with me and record pop data while they had my Arc in “devmode”, which provides detailed recordings and diagnostics to Sonos.

I produced multiple on-demand pops, on Xbox, on Apple TV, and even on the Apple TV screensaver when no sound was playing; and submitted the recordings. I have not heard back since. Here is the link:

https://en.community.sonos.com/home-theater-229129/sonos-arc-loud-pop-then-audio-loss-6852340/index21.html?postid=16633668#post16633668

I am not the only user that can easily reproduce the pop. Just put on a Spatial Audio playlist on Apple TV and you should get it within 30 minutes. We have also had reports of at least one user in this thread that was affected by the pop and never had a peripheral connected. It was coming straight from the TV which uses Dolby MAT, a rarity for TVs of course.

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Hi @William_61 et al

We are aware of this behaviour and are investigating it, but we do not have any additional information to share on a resolution at this time. 

We are also aware of other manufacturer brands experiencing the same problem. Some users have reported it with in-built TV apps, so it is not limited to X-Box and Apple TV owners.

The issue only happens when playing Atmos content, so in the meantime, you can prevent this from happening by disabling Atmos audio on the TV or source device - not ideal, I know, but if it has happened to you before and you are concerned about it happening again, this step would prevent it.

I hope this helps.

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I haven’t yet had time to test the software fix, holidays and all. Do we have reports from affected users yet if Arc/Beam2 are fixed now?

I’ve been using Arc and beam Gen 2 since the update and no pops yet 🙂 true play has been rerun as well (coincidence as changed the room layout slightly) well done @Corry P @Mark.Wi and team. So far fingers crossed

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Been watching & listening to Atmos content all weekend thanks to receiving the long awaited Sonos Arc fix and the heavy rains. No issues at all and the sound has been terrific. 
 

Set Up: Sonos Arc, Era 100 Surrounds, Sub Mini, Apple TV4K, Sony X900H
 

Thanks to everyone who’s gone out of their way over the years to troubleshoot and help folks through home brew fixes. A real community effort. Thank you also to the Sonos engineers who finally were able to figure out this complex issue. Cheers to all of you! 🍻

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Bingo! I captured and submitted an Xbox pop as well.

I’ll stop now as this is quite time-intensive work. I’m looking forward to hearing what insights come out of this process. 

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here’s the latest official response from Sonos support, which seems to suggest it’s specific to some TVs. I know Microsoft has been working on a HDMI 2.1 problem with the Xbox Series X on certain LG OLED models, where the console would boot up into a resolution from 1995 instead of 4K.

 

Either way, we’ll get on to Sonos and figure out if this is TV specific or something related to Dolby MAT 2.0.

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Over a week has passed, I’ve been using Apple TV and Xbox plenty with Atmos on, and there has been no pop. It appears that CEC-off on Xbox plus power cycling all around has solved the problem. It’s a little annoying that I now have to use the TV remote for input switching and power on/off when using Xbox, but that’s OK. More importantly my family can use Apple TV with just its remote and CEC works fine.

I have to add that I am surprised how much better I feel when watching movies and playing games. I didn’t realize just how much stress and frustration pent up from having dropped thousands on a sound system that didn’t work for its advertised purpose and, perhaps worse, where the manufacturer spent years aware of the problem and still hasn’t publicly acknowledged it.

Will I ever buy another Sonos product? I don’t know. But I’ve learned my lesson that it’s more like AliExpress than the reputable brands (Denon, Klipsch, Sennheiser, etc) from which I typically buy.

If I don’t post in this thread again for a while, bon voyage, fellow forumers. I hope your problem is resolved as well. You have been troopers sharing information, replicating, troubleshooting, etc. Yes, there are a few users who tried to throw us off the solution path through persistent gaslighting that the problem didn’t exist or surely couldn’t be Sonos’. But you all hung in there and we’ve made it. You will always have my thanks.

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