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

Further to this, wondering how many other sound bar / reciever users use their TV as a passthrough mechanism.  When looking at the specs of them generally the devices connect directly to them opposed to using the eARC on behalf of all HDMI ports.  
 

This obviously is a discussion we have never had with the Arc / Beam only having a single inout HDMI allowing only a passthrough configuration but it could be why other soundbars / receivers seem unaffected

My god the amount hubris…. I can’t even reply to this absolute nonsense. 

As it stands now the end user is suffering and Sonos seem unable to fix the issue. Perhaps they are hoping that Apple and Microsoft can fix it for them, Or LG,Samsung,Sony and other TV brands fix it for them.Or maybe they are hoping that Dolby themselves will fix it for them.

Currently ARC owners may as well just be using a Playbar and Beam Gen 2 owners may as well be using the Gen 1 as we cannot really use Atmos. Now I own both the Apple TV 4K and the Xbox Series X and it really is an unacceptable end user experience.

It really is time this problem is sorted out or simply refund us for our purchase so we can move on to something that does work. 

Sonos has been telling us for 3 years that they can’t reproduce this Arc Atmos BANG issue in their labs. An issue and topic of probably their largest complaint thread on the Sonos Community ever.

I know it sounds crazy and would never happen, but if Sonos was truly interested into getting to the bottom of something they can’t replicate, why not find 3 users who’d be willing to sell their TV, Apple TV, XBox & Arc sets ups to them? Sonos could then have the set ups professionally packed & shipped to their labs? They could then do all the BANG testing they’d ever need. Could be the best $20K their R&D ever spent and could finally put this issue to bed. 

You’d think they would be able to find out what’s going on based on the diagnostics we’ve all sent them. A month ago I was told they were looking into it yet here we are and their support that reached out to me has been avoiding me now. 

Believing that load of nonsense is the same as believing the story that it’s the front end supports first time hearing about this issue.  Sonos knows exactly what’s going on and how to produce it.  

Thank you all for the support (special shout out to @professorfang who has been quite active on this issue). 

I think that’s a great point @TheFlamesFan - I certainly think it is reasonable to consider any part of the chain from MAT encoding at the streaming device through to the decode process at the Arc/Beam in the spirit of keeping an open mind and trying to legitimately solve this issue. That said, if reports from other users that this persists when using the 4K Arcana, it makes me a little bit more hesitant to attribute this to pass-through issues with the TV, as from my understanding, that device is as close to a gold-standard for passing through all formats of audio via HDMI. Again, if Sonos made any effort whatsoever to share information gleaned from the litany of diagnostics we have sent in over the last three years, perhaps we wouldn’t be forced to speculate as much.

I would also add one more point - even IF this is an issue that is not related to how Sonos decodes MAT and handles that content (be it upstream issues with eARC and/or CEC (when enabled) or errors in timing from BOTH the XBox and ATV encode process with MAT), Sonos still could make changes in how these errors are handled. I would far prefer if there were brief audio drops when there are decoding/processing errors with the Arc/Beam as opposed to a MASSIVE gunshot sound that wakes up my entire house, scares me to death, and makes me worried it might ultimately blow out a speaker. It would be an incremental, though substantive improvement if Atmos content did not result in such a catastrophic breakdown specific to Sonos products. I’m scared to even enable Atmos to do testing because the noise is so loud that I’m on edge the entire time (don’t even get me started on the terror it induces for our cats).

Couldn't agree more, perhaps other soundbars have had the same issue and have far superior exception handling routines over Sonos and are able to gracefully recover without hinting to the user that something is wrong.  

I think the community would welcome that fix if it were at all possible

You know, it didn’t even occur to me that this should be the case but now that you’ve said it, it seems obvious.

Sonos, please AT A MINIMUM make this happen.

https://www.reddit.com/r/sonos/comments/14pupmm/extremely_well_done_post_on_the_nature_and_causes/jrevwxe/

Sonos rep replied to the Reddit thread covering @rc12 ‘s post.

I appreciate the post but still does not give the warm and fuzzies that this issue will ever be fixed.  
 

Probably in the line of expectation of a $200 soundbar kit but certainly not in line of a $2500 setup.

Sonos needs to do better and offer assurances to its loyal customer base that they will fix the problem or take back their problem hardware

Long time Sonos user here. I recently upgraded my living room tv and surround sound to this combo:

LG G2, Arc, Sub Mini and Era 300’s. I have the most recent Apple TV4k that does all of the streaming for me, with the exception of Netflix (I use the LG’s webOS because Apple TV won’t do Dolby Vision or Atmos with Netflix). Anyway, I have been getting popping, creaking noises from the Arc since I upgraded.  At first I thought it was the TV getting warmed up, my last TV would do that until it was at full operating temperature.  I get the popping noise even when no Atmos content is playing. The Apple TV screen saver is active with no music playing and I still get cracks, pops and a creaking noise. About 30 minutes ago I turned Dolby Atmos off in the ATV settings and I’m still getting cracks, pops and a creaking noise.  Even with the ATV completely powered off, while watching cable tv, the popping noises are still happening.

This is unacceptable. I have spent a lot of my hard earned money with Sonos. Does anybody have any recommendations for an Atmos capable sound bar, sub and rears that plays nicely with Apple TV?

You shouldn’t be getting pops or creaks with the ATV powered completely off.  This sounds like a defective unit rather than the specific “popping” issue that’s being discussed in this thread.

Honestly, I would do some more troubleshooting and pursue a warranty replacement before ditching the entire system. 

I’ll look into getting a warranty replacement after I get video evidence of the noise with the ATV unplugged. 

You said you just upgraded it?  If it’s still under the retailer’s return period I wouldn’t even mess around with a warranty replacement.  Arc would go back in the box for a quick exchange at the retailer.  As you said, we spent a lot of money on this gear and it’s not unreasonable to expect it to work straight out of the box.

Adding my identical experience to this thread. 
 

Sonos Arc. Xbox Series X with Dolby Atmos selected. CEC disabled. LGC1 utilizing eArc.
 

Loud pop (like a gunshot) whenever I leave a game running Dolby Atmos and return to the Xbox dashboard. Horrifying every time. 
 

Grateful for RC12’s advocacy on this thread.
 

C’mon Sonos.

Cleary, you have identical hardware and setup to me.  If you disable “Dolby Vision” and “Dolby Vision for gaming” on your Series X.  Do you get the pop? 

Will try it out tonight and report back. Am hopeful after seeing your post. Thanks for the message. 

I have never had Dolby Vision enabled on my TV side for Xbox and I get the nasty pops on my Sony OLED. 

This has been ruled out as a fix a while ago. Sadly, there is no real fix on our end as it has to come from Sonos. 

Hi. I came across this post from Reddit. I just had this “pop” issue with my beam gen 2 while watching the new transformers movie on my Apple TV 4K and Sony 900h. This has never occurred with any other Atmos streaming. I haven’t changed any settings either. What’s the troubleshooting for this? Or am I understanding that there’s no fix and I own a brick now if I want to play atmos content?

Some users here have had success with turning off Dolby Vision or turning off CEC. Neither has worked for everyone.

Official Sonos recommendation is to turn off Atmos on the Apple TV. That works for sure but, you know, sucks. 

Update: turned off Dolby Vision on my Xbox Series X and played a couple hours with frequent jumps back to the dashboard. No gunshot pop sound as of yet!…

Xbox Series X in 4K/120fps mode with VRR. Both CEC and Dolby Vision are disabled. Dolby Atmos back on. Sonos Arc and Sonos Sub (Gen 3). LG C1 with Sonos Arc on eARC, Pass Through, Bitstream. SIMPLINK-CEC on LG C1 set to On,

Total conjecture: does some credence to the idea that the Xbox with 4K 120fps VRR Dolby vision is hitting the LGC1’s 40 gbps HDMI 2.1 with the Dolby MAT encoding on Dolby Atmos. Maybe?

Will keep testing (ie gaming for science)

Anyone tried the firmware update from today? If there are imrpovements. In the process of getting settled in a new apartment. Just got an LG C2 - but haven’t yet hooked up my arc. And I use Apple TV 4k. At my last apartment with an entry level LG TV I didn’t have any problems.

Glad to hear, figured it was worth trying seeing that you have identical hardware to me and get the pop in the exact same scenario I do.  
 

Certainly leads to some interesting theories as to why the particular hardware configuration behaves once Dolby vision is removed.  Does anybody have the pop on a LG C2 or C3?  To expand clearys theroy, those TVs have 48 gbps ports while the C1 only has 40 gbps.  The configuration above 4K/120 10 bit colour literally consumes all 40 gbps (actually more seeing DV is 12 bit colour, tunneled back to 10 bit)

Ive also never tested with 4K/60hz and DV on.  But kinda scared to make changes now that it is behaving