We did have a user many pages back that was affected and had a TV that used Dolby MAT for output. No Xbox or Apple TV had ever been hooked up. 

Both gunshot pops (rapid fire) and single pops, mixed and unpredictable. At times it sounded like electrical pop sounds and I did jump to the conclusion that something had blown the Arc speaker(s) until the reset and fantastic sound since. 

Even triggered some Pops while unplugging to try a reboot and accidentally touching the volume buttons on top, so even the interface sounds could generate pops instead of the intended sound. 

I didn’t notice the audio codec but it was popping for anything that we threw at it: both Sonos Radio Rock Pantheon music (and any other stations), Amazon Music, and local CBS television which was likely DD5.1 at that time.

I didn’t know about this and similar threads during the bulk of this, so I can’t say for sure that we threw any ATMOS source at it. But definitely no AppleTV, no Xbox and CEC was turned on (controlling volume up & down with TV remote) and spatial or ATMOS (whichever it is) in the S2 app was also turned on. The former two seem to be getting lots of redirection blame for triggering pops but this was direct HDMI eArc connected to a mid-brand TV. The remedy I’ve read is to turn CEC and spatial/ATMOS off but that seems like a terrible remedy given both are KEY benefits of Arc.

Again, all sounded great for a couple of hours in which I couldn’t run Trueplay due to some uncontrollable environmental noise in the area. After that was silenced, I ran it, expecting Trueplay balancing as I had done several times with another Arc and Move speakers... and that process was immediately followed by Pops (singles and rapid fire). After several restarts, it was the same.

Only sleeping on it and then trying factory reset, setting ARC back up again, linking it with the two 300s again, etc (basically everything I had done the night before EXCEPT running Trueplay) brought back excellent Arc sound with both music and television. Been pounding it all day & evening since yesterday with all kinds of sources included confirmed ATMOS stuff from Amazon app on that TV and not a single pop. Everyone is gushing how great it all sounds (as we all expect from Sonos). 

While it’s terrible to jump to any conclusions on only one instance of any cause & effect, my gut feel is that if I ran Trueplay again right now, the Pops would immediately follow and the whole process would have to be redone again to get back to the great sound I have now. While one should never pass judgment in one instance, those same guts say this problem MIGHT be centered in Trueplay, which in the setup process is something people are told to run. In my case, I bailed on the initial setup process at that point due to some noise I couldn’t control (waiting for silence before running Trueplay). And that led to this potential discovery that may prove to be helpful for others. 

Hopefully, a few with the Pops can recall running Trueplay and opt to give this a try. Resetting to factory is easy, as is setting the reset speaker back up again. When it gets to the Trueplay step, bail on the process and try playing something you know was making it pop before (and play something through AppleTVs and/or Xboxes too). If a few people can confirm this possible remedy, Sonos could dig into the Trueplay programming to find what I suspect could be some selective bugs that basically lead to the pop problem for some of us. 

Some programming bugs makes much more sense (to me anyway) than “turn off ATMOS” or “turn off CEC” for THIS speaker… and it seems doubtful that Apple, Microsoft and select TV manufacturers would ever alter their audio playback hardware or software to “fix” this problem for Sonos if it was really them.

I’ve run Trueplay on my own Sonos stuff several times and never had the problem, so perhaps it’s also linked to select combinations of Sonos speakers? In this case, I had already linked an Arc and two 300s in a single room before running Trueplay. Maybe that’s one of the combinations that can trigger this?

Again, perhaps I’m onto nothing here (a good scientist would run cause & effect several times to see if- in this case- running Trueplay again now would bring those pops back without changing anything else (I suspect it would)), but we enjoyed the same CBS channel likely playing Dolby 5.1 for stretches of time before I ran Trueplay. So if Dolby MAT is at fault, it would seem Arc should have been popping before Trueplay ran too. Sounded great… right up until I ran Trueplay.

After that, every audio source made it pop, including Sonos own radio stations, which are presumably NOT Dolby MAT, nor even running through the television at all (wouldn’t Sonos radio just direct play on Arc via ethernet connection to router?). I use an Arc in another room for music only- no TV connected at all- and listen to Sonos radio on it frequently (has been trueplayed several times over the years and never had any pops).

And again, since the reset early yesterday, the otherwise exact same setup, cables, TV, etc has been playing near non-stop- including more of those local TV stations- with not a single pop. So if Dolby MAT is at fault, it seems there would have been lots of pops when running stations playing Dolby Digital. What’s different since yesterday? The ONLY thing: Trueplay has not been applied.

New Arc owner here. With Sony now rolling out the PS5’s Atmos update, should I be cautious of using that mode for audio output?

Based on what I have read on reddit, yes. The PS5 uses Atmos via MAT as well, which appears to be the cause of the problem.

Yes, beta users here reported the pop after switching to Atmos.

Possibly MAT processing sets a bit(s) somewhere outside of its bounds that sometimes causes issues for something else. Once there was a Mars lander crash because one routine got its one/zero origin mixed up,

---

For non programmers: Array (list) elements are reverenced by a number. Some schemes start the element ID’s at zero (#0 is the first element), other schemes start the ID’s at one (#1 is the first element). There are advantages and disadvantages to each scheme and ultimately it does not matter much which scheme is used -- unless the ‘other’ scheme is used somewhere along the line. For example Programmer ‘A’, using one origin, will call for element #1 (the first element), but this will be the second element in Programmer ‘B’ scheme of zero origin.

In this case an invalid reference could sometimes modify a single pixel in a graphic, but other times could result in output volume set at beyond infinity -- resulting in a ‘thump’ and amplifier shutdown. These things can be extremely transient and hard to track down. I’m glad that I’m not working for SONOS, tasked to fix this, and I sympathize with users who are suffering.

Never thought I’d see an explanation of zeroith vs first indexing on an audio site, but there  you go. 

UPDATE: FIVE DAYS LATER

...with all variables the same and no pops. The idea that the TV may be pushing Dolby MAT causing pops doesn’t seem to be applying… else we’d still be hearing pops. Working against a retail exchange window, we’ve been pounding these speakers day & night, basically trying to cause the pops again from all audio sources, including ATMOS and there’s been no pops. CEC is ON and working fine. ATMOS/immersive in the app toggle is ON too. The ONLY variable that I suspect drove the pops that has still not been run again: Trueplay.

On that first setup, Trueplay was delayed for a few hours and Arc + Two 300s setup sounded great for those hours. Then Trueplay was run and there was immediate pops, sounding like speakers were blowing/blown, rapid fire and single pops. Reset to factory, set it all up the exact same way again but did NOT run Trueplay. No pops since. 

Anyone with pops: I encourage you to test this hypothesis, especially if you can make the pops happen in a predictable way: some particular source, music, video. Reset the popping speaker to factory, set it up again but when you get to the Trueplay part, bail on the setup process. Then play whatever caused it to make the pop sounds before this reset. 

If this problem is centered in a variety of other manufacturers hardware- AppleTV, Xbox, select TVs, Playstation, etc- how is it ever going to get resolved? Those players are not likely to all adapt their audio output to fix this Sonos issue “affecting a small number of individual users.” 

On the other hand, if it is a software thing- which makes so much more logical sense than blaming many others and/or “turn CEC off” and “turn ATMOS off”- debugging some software has the potential to fix this for up to everyone affected. 

While this guess has great potential to be WRONG as it is based on only a single instance of cause & effect, my guts say there may be a solution in waiting here… unlike getting Sony + Apple + Microsoft + various TV Manufacturers + <who else> to change their audio outputs. Whether complete or only partial, at least it would be something Sonos could potentially remedy by their own actions. 

If anyone is willing to reset to factory, set up again and then see if the pops continue, post your results. This weak guess could be wrong but if it is towards right, it would give Sonos somewhere to focus some attention. These speakers sound so freaking good without the pops. I hope others with this problem find a path to enjoying them too. Maybe this one? Maybe something else?

I’m using a Beam Gen 2 with an Apple TV 4K 2022. I haven’t had pops like people in this thread describe, but have suffered audio dropouts every 5-10 mins when using Netflix with Dolby Atmos enabled. If I select Dolby 5.1 the pops go away, so I suspect this is the same issue.

we watched three episodes of a show last night and there were regular audio dropouts throughout. So I’ve taken your advice and have reset the Sonos and set it up again without Truplay and so far so good. We watched two more episodes and had no dropouts at all.

Obviously early days but seems promising so far. I’ll test for a few more days and report back.

i also encourage others to give this a go and report your findings here.

What would really be a good test if you can stand it is watch the same 3 episodes again (or at least put them on and listen for the same audio dropouts). That would have every one of the very same variables in place EXCEPT Trueplay. If there are no audio drops with the exact same signals, this concept of “blame AppleTV” or “blame ATMOS” or “Dolby MAT” etc starts getting more meaningfully undermined. And the confidence that perhaps it is something in the Trueplay algorithm that needs Sonos attention would rise.

Thanks for going to the trouble of at least trying my guess. Hopefully a few more with such issues do too and we begin to see a pattern that could lead to an actual remedy vs. expecting a bunch of other players to do something and/or “don’t use ATMOS” and/or “turn off CEC.” 

Not actually that difficult as I was watching The Good Place on Netflix and each episode is only 20 minutes long. Watched them through again today and no audio drop outs. Fingers crossed you’ve stumbled across something here. We’re also watching Stateless on Netflix which also gives lots of audio dropouts. Will probably watch a couple of episodes tonight so will report back.

Unfortunately I spoke too soon. We had dropouts last night. The weird thing with our Beam is that it keeps dropping the dialogue track but you can still hear the environmental sounds, traffic, birds, rain etc. Sometimes it will drop the dialogue track permanently until you switch Dolby Atmos off.

Arc + surrounds + sub + Apple TV 4K + LG C2 - I’ve had the popping off and on once a month or so, but have the dialogue audio dropouts even more frequently. Most often with Hulu. Super annoying but it never dawned on me that it could be SONOS related as well.

I only made the connection because I couldn’t execute the usual process… which flows right into Trueplay as part of initial setup. In this case, I had to bail on Trueplay until some noise beyond my control was silenced. So I experienced what might be called an audio quality sandwich:

• Great Sonos sound via Arc & twin 300s for a few hours until I could run Trueplay
• Then pop-a-rama from Arc from the same sources that had just sounded fine starting immediately AFTER running trueplay... until I reset to factory
• Then great Sonos sound again because I haven’t re-run Trueplay. A full 8 days in now and all sounds as good as any of us expect from Sonos.

My instincts tell me that is it MORE likely the problem is with Sonos than all this third party redirection. For example, the source never changed here, so the “Dolby MAT” redirection claim should have yielded the same negatives heard in the middle part of the sandwich. It sounded great (perfect?) before & after. Only after running Trueplay was it pop-pop-pop unusable from the very same sources through the very same HDMI cable, with the very same settings set. 

The “don’t use CEC” and “turn off ATMOS” redirect makes no sense either. Else everyone would have the problem vs. only “a small subset” and aren’t both of those just about the point of buying Arc? Why buy an ATMOS soundbar to not use ATMOS? Does anyone want to separately control volume on soundbar instead of using the TV remote?

Blaming AppleTV and Xbox, etc would mean the problem is unsolvable because it seems unlikely those other players will ever modify their audio output to fix this problem affecting “a small number of Sonos users.” 

I have another Arc + Move paired in a room. Both have had Trueplay run several times. No pops at all… but I only use them for music in that room.

The new one paired with twin 300s popped on ALL sources, including Sonos’ own radio channels… and even popped with button presses on the Sonos Arc itself. I’m doubting that Sonos would code their own music and UI sounds wrong to trigger the pops.

So I continue to see the ONE unique variable as having some potential for resolving the “pop” issues described in this thread. Anyone interested in testing, reset to factory, set up again and bail at the Trueplay step. Then see if your reset speaker will pop on anything that made it pop before (same video, same music, whatever caused pops). If you can find a few things that makes it reliably pop every time, test with those same things (same video or audio) after NOT running Trueplay on a reset Arc setup. 

Maybe the audio dropout problem is separate from this? Maybe this is only a discovery for certain pairings of Sonos things like Arc + 300s? Or maybe there’s nothing to this but curious coincidence: sounded fine for a few hours, pop-fest for a few hours- sounded fine for the last 8 days now? For me, all variables are identical except for one: no trueplay run = fantastic sound with no pops in both buns of that sandwich.  

Maybe a simple test can help others too? If a few more will test this and find that it works, Sonos would have something to immediately work on (presumably a bug(s) in Trueplay) to potentially solve this for many with a software update and (fixed) Trueplay re-run. 

Your account seems more repeatable than others that I’ve read. Submit some before and after diagnostics, keep a log and contact Support. They might want to enable a special diagnostic on your system.

Just experienced two pops today for the first time, have had my Arc+One+OneSL for a few years. I thought it was a bird hitting the window until the second one.

The biggest change, recently moved to an LG C3 from a Samsung Q9FN. Since getting the C3 we used the webos apps, but I realized this week a bunch of the LG streaming apps don't offer Atmos but on Xbox they do. Started using Xbox Series X again, got two pops today, both while navigating around.

Definitely had Atmos working on the 2018 Samsung at times (not earc or full hdmi 2.1) so it seems to be some combo of the earc/LG, Xbox, and Sonos for me, and potentially while pressing universal remote buttons to navigate UI.

In my book, it still points to the issue as mainly involving the multi-channel LPCM (container) format where the Atmos metadata is sent alongside the lossless audio stream - so my money is still on the Atmos metadata falling out of sync with the stream and sometimes creating that noise, which you describe as ‘a bird hitting a window’. Maybe it’s devices en-route like the TV and/or cables causing this anomaly too, as clearly it doesn’t happen for everyone and it explains why some users may find solutions when changing a cable or introduce an audio extractor into the path and bypass their TV etc.

I don’t personally use LPCM for Atmos playback, as I don’t have the hardware that supports it and so far I’ve not heard the noise and that’s with an LG TV too, albeit the older C9 TV.

Again, I’ll share that once Trueplay ran and the Pops began, it was not an occasional thing as described just above and Arc would pop whether watching ATMOS or playing Stereo Music (including Sonos own music stations) or even using the buttons on top of Arc and getting audio feedback from presses. 

It’s easy to redirect to “it’s <other parties> fault” but how do we rationalize such speculation against the  experience of NO ATMOS, no Xbox, no AppleTV, etc? Is there any ATMOS at all in Sonos radio stations? Is there any ATMOS in UI audio feedback sounds from touching Arc buttons?

Similarly blaming cables and other devices is fine but in our case we had pop-free audio from ARC for a few hours BEFORE running Trueplay… then pop-FULL audio after Trueplay (no matter what we threw at it)… and then a return to pop-free audio after factory resetting and NOT running Trueplay again. All same sources tested. All same cables. All same settings. If the cause is cable or settings or TV, how can we have pop-FREE periods before and after applying Trueplay (for coming up on 2 weeks now)?

whippleshuttle’s post is interesting in that apparently the only variable that changed was TV type. Apparently, one TV subbed in for another, presumably re-using the same cable and otherwise all of the same stuff, services, settings. If so, that undermines my (wild) assumption that maybe Trueplay has some bugs to address and adds something to the chorus of some kinds of differences in how ATMOS (and DOLBY MAT, etc) are implemented. I’d be interested in knowing if in replacing the TV, did whippleshuttle change any other variable… particularly did they re-run Trueplay? Or use a new cable? Or replace any other supporting hardware at the same time?

Nevertheless, in my experience, where there is a great diversity of possible causes, a good strategy in finding the actual cause is to narrow in on the common elements. What does all such scenarios have in common? That is probably not one cable or one TV or one setting, etc. My gut says scrutinize the common denominator much harder first before then working out into what would seem to be quite diverse- even unique- variables of specific TV, specific cable, specific ancillary hardware, specific services, etc. 

And, of course, there’s always fair possibilities that it is combinations of things that leads to an answer too. If everyone had the POPs, Sonos would have to stop selling the product because the noise and press would sound far louder about the issue. In my case I have a perfectly fine Arc + Move paired on which Trueplay has been run a few times during it’s many years with me- no pops at any time over those years. This other brand new Arc + twin 300s was popping like crazy after Trueplay was run on it. Is Arc + Move somehow immune vs. Arc + twin 300s? Or if I swapped the Arcs and ran Trueplay on the no-pops-ever one now paired with the 300s, would it suddenly start popping? If it was my job to figure this out, I’d try that. But since I now have both setups sounding fantastic, I don’t feel motivation to stir either pot.

Interesting point actually, not a scientific test but the pop did not occur until I switched to Monoprice cables. 

Changing the cables will refresh the CEC settings so it’s possible that this tripped the same issues that we have talked about in this thread 

Same issue as everybody in this thread with an Apple TV 4K. Get in touch with Sonos support this morning, they’ve told me everything is fine with my Arc from the diagnostic. They are aware of the issue but it seems they don’t have a solution at the moment.

Not the best case scenario for Dolby Atmos customers.

Brand new customer with LG C3 OLED, ARC, Sub Gen 3 and 2 ERA 300s.  Had this happen to me twice last night, sounded like the Arc was going to explode.  The status light was flashing on it as well.  Sound eventually came back, but I was worried to use it anymore.

I use my Windows 11 PC over HDMI to the TV to play video games - was playing Cyberpunk 2077 with Dolby Atmos turned on and with 4k gfx.  Support says they want me to submit diagnositcs after it happens again but I’m like damn...what if it damages the speaker?  Hope they would cover it if that’s their advice

To be honest, I no longer know whether to laugh or cry. The mere fact that the error has been going on for much longer than the entire Covid19 pandemic…

The error will then be fixed shortly with the release of Arc 2

Has there been any updates I’ve missed, this thread has died lately.