Hi @throwawaybeam2 

Welcome to the Sonos Community!

As you have experimented and found this to be repeatable, I recommend you get in touch with our technical support team directly so they can take some diagnostics and gather information regarding this occurrence. Thank you. 

Hey @Corry P 

I checked the link and unfortunately my country is not listed on the dropdown so I can’t call and chat indicates that there are no representatives available.

For anyone with a PS5 who would like to test the issue out, you could do the following. No need for a bluray film / game as you could test it simply with the audio that’s playing on the background of the settings screen:

• Go to Settings→ Sound→ Audio Output→ HDMI Device Type→ Set to “AV Amplifier”
• Go to AV amplifier→ Number of Channels → Select among 2 ch, 5.1 ch, and 7.1 ch
• If you select 7.1 ch or 2 ch from the dropdown on the PS5, Multichannel PCM 7.1 / Stereo PCM will be reflected on the Sonos S2 App. Listen to the background audio and there should be no issue.
• If you select 5.1 ch from the dropdown on the PS5, Multichannel PCM 5.1 will be reflected on the Sonos S2 App. Listen to the background audio and there should be consistent audio dropouts once every 1-2 minutes.

I guess you could also test with a PC or any device where you could force toggle between Multichannel PCM 5.1 and 7.1.

Hi @throwawaybeam2 

Please recreate the issue and submit a support diagnostic, replying here with the number given. Thanks.

Diagnostics: 1458431194

As I have no idea how Sonos gathers the data, I had my setup run for 5+ minutes where the issue appeared multiple times. I hope it’s enough.

It’s a really weird issue as I’ve tried out various Dolby and LPCM formats since updating to 14.10 and it only appears on Multichannel PCM 5.1. The only format I’ve been unable to test is Dolby MAT Multichannel.

Hi @throwawaybeam2 

Thanks for the diagnostic. The Beam is reporting underflow errors, meaning that the audio is being interrupted before it reaches the Beam. As this happens with two source devices, the source of the interruption is likely the TV itself, or the physical connection between the TV and the Beam.

If you haven’t done so already, please unplug the TV from power for at least 2 minutes. In the majority of cases, this simple step usually fixes such issues. I didn’t mention it before as you mentioned installing a TV software update - this would include the TV rebooting it’s software. Perhaps it’s the hardware that needs to restart instead.

If this doesn’t help, please swap the ends of the HDMI cable linking your Beam to the TV - put the end that’s currently in the TV into the Beam, and vice versa. Also, are you using the cable that was supplied with the Beam? If not, please do so. If so, please try another (HDMI 1.4 or better).

I hope this helps.

Hi @Corry P 

I’ve already tried unplugging both the TV and the Beam on my previous tests. As per your suggestion, I unplugged both again to no avail.

As for the HDMI cable, I am using the one that was supplied with the Beam. I just tried your suggestion of switching the ends but alas the issue still persists.

It’s really weird though that Multichannel PCM 5.1 would fail when Multichannel PCM 7.1 works. Would be easier to understand if it was the other way around. And Multichannel PCM 5.1 is something that worked flawlessly prior to the Sonos 14.10 update.

As I have made no changes to my setup except for updating my Sonos to 14.10, I am inclined to believe that it may have introduced this weird bug. I also haven’t moved any device / HDMI cable physically. As mentioned, I have already discovered the issue before I updated my LG C1 so it should have no bearing. So Sonos 14.10 really is the only change on my end.

Edit: Is it possible to downgrade back to 14.8 so that we can conclusively tell if the issue is with my setup or with 14.10?

I don’t have an Xbox, but 5.1 multichannel LPCM audio is working okay for me albeit from an Apple TV 4HD connected to a slightly older LG C9 TV with Arc, surrounds & sub. No audio interruptions/dropouts. TV digital audio-out is set to ‘pass-through’, rather than ‘auto’ in the LG sound settings.

Maybe try toggling the TV audio-out settings and perhaps consider removing anything else connected to the other TV HDMI inputs (leaving just the Xbox & Arc connected) to see if that might make any difference. 

Hey @Ken_Griffiths 

Thanks for responding. I’m on PS5 and Beam 2, but yeah. My LG C1 is already set to Bistream / Passthrough / Earc On. It’s really weird that LPCM 5.1 would get bugged when LPCM 7.1 works just fine. And I was able to use LPCM 5.1 just fine right before updating to Sonos 14.10. 

Sorry as I don’t have an Apple TV device, just wanna confirm if your Apple TV outputs as the normal LPCM Mutichannel 5.1 and not Dolby MAT Multichannel 5.1. Also, are you already on 14.10?

Hi @throwawaybeam2 

I confess I misread your initial post and thought two sources devices were involved, but I see it was just the PS5 and either games or movies on it. We would ideally like to check another source capable of 5.1 PCM, but if you don’t have one that can’t be helped. There was a PS5 update on the 12th of May, so we can’t rule out either that update or our own until we can reproduce the problem, or not, with another source.

I take it you have no issues with built-in TV sources like channels or apps? I don’t believe they would provide 5.1 PCM, so it seems likely, but please check if you haven’t already.

Given that other formats work without issue, including 7.1 PCM, I think we can safely rule out the cable - something that should have occurred to me already. My assumption at this point is that it is a software problem - I’m just not sure who’s, as it could be Sony, LG, Sonos or a weird combo of all three. I’m going to flag this with a colleague to see if we can reproduce this ourselves.

Hi @throwawaybeam2 

OK, that did not take as long as I thought it would - my colleague spotted some issues happening on the CEC network and suggests you factory reset your TV. A HDMI CEC-less adaptor between the TV and PS5 should prevent it happening again long-term.

I hope this helps.

Hi @Corry P 

Really appreciate your fast responses. I actually did some more testing and was about to share them here but I see that you have an updated recommendation for me. I would like to ask if you could reassess on your end first using the updated info that I will share before I factory reset the TV as it such a hassle to set the TV up again if it turns out that it is not the issue. Thanks for understanding.

Some responses first to your second to the last post:

• The PS5 did have a minor update last May but as mentioned I was able to use LPCM 5.1 with no issue just 2 weeks ago before updating to Sonos 14.10 so I don’t think it’s the culprit. As for another source, more on that in a bit…
• I have no issues with built-in TV apps  (stereo, DD+, atmos, etc)

Now, as for another source… I do have a PC connected to my TV via HDMI 2.1 (eArc out to Beam 2). I mostly use it for gaming and haven’t gamed on it for awhile now (mostly focused on PS5). As I didn’t even have a single game installed, I initially focused my testing on PS5 and stopped once I was able to reproduce the issue.

But since I’m now getting desperate (I really want to resume watching my blurays!), I tested things out on my PC and discovered that no matter the source audio, my PC will “wrap” and send over the audio on whatever format I select under PC Sound settings. So I could just, say, play a video on Youtube from my web browser and even if the source is Stereo, my PC will wrap and send it over using the format I specified in the settings. Results are as follows:

• Audio set to Dolby Atmos for home theatre - youtube vid is being reported by Sonos S2 App as Dolby Atmos, the MAT kind. No dropouts
• Audio set to 7.1 channels - youtube vid is being reported by Sonos S2 App as Multichannel PCM 7.1. No dropouts
• Audio set to 5.1 channels - youtube vid is being reported by Sonos S2 App as Multichannel PCM 5.1. First dropout occurred within 40 seconds!

From my PC and PS5 tests, it is clear so far that the audio dropouts only occur when the Sonos is reported to have been receiving the Multichannel PCM 5.1 format. So I would to ask for you to reassess again if the TV really is the culprit as it is a hassle to set it up again and so far the only change with my setup is updating to Sonos 14.10. You mentioned HDMI-CEC in your last post and while yes, my PS5 has HDMI-CEC set up with the TV, the PC cannot be linked via HDMI-CEC to the TV (power sync, send control inputs, etc) yet the same issue is happening when using the PC.

Hi @throwawaybeam2 

A good test would be to play 5.1 PCM from the PC, but without the PS5 connected to the TV, and after a TV power cycle - if the issue doesn’t occur, then disabling the PS5’s CEC  options would be a good place to start, then try a CEC-less adaptor if that doesn’t help. Having said that, I’d still recommend trying the free option of a TV reset before spending any money.

If, however, the PC gets interruptions without the PS5 connected, then I recommend the reset of the TV.

If neither resetting the TV nor disconnecting the PS5 fixes the problem, it really would be best to get a case created by getting in touch with our technical support team via chat or email.

Hi @Corry P 

I unplugged the TV, unplugged the PS5’s HDMI cable from the TV, waited a couple of minutes, and then played 5.1 PCM from the PC and a dropout occurred within a minute. So it’s probably not it.

It may be hard to convince people to factory reset their other devices (esp if it’s a hassle to set it up again) or spend money on additional 3rd party devices when a Sonos firmware update is literally the only thing that changed with their setup. My 5.1 LPCM setup worked days before I updated to Sonos 14.10 so I am really inclined to believe that that caused a weird software issue with LPCM 5.1 considering that literally nothing else in my setup changed and all other formats work (including the heavier LPCM 7.1).

Is there a way to downgrade to the previous firmware? Because that’s probably the easier way to tell if 14.10 did mess things up.

Hi @throwawaybeam2 

I don’t disagree - the timing with the update is worthy of note and we did alter some Home Theatre functionality in said update (though I don’t know if any of it pertained to 5.1 PCM specifically and only - it seems unlikely). I’m certain, however, that a reset of the TV is the best way to get the troubleshooting process to move forward, at the very least, given what the engineer I spoke to told me about what was found in the diagnostics.

There is no way to roll-back the software (I don’t like to speak in absolutes because many things are technically possible, but to all intents and purposes it can’t be done).

Hi @Corry P 

Really appreciate all the support I’ve received so far even as we’ve not been able to achieve a satisfying conclusion. I am done with this for now as I’ve pretty much spent an entire day working on this. At this point, however, I am of strong belief that this is a weird bug caused by the 14.10 update.

I don’t know if I’m just unlucky or if this is actually an undiscovered issue affecting multiple users as it is not part of the common use case. If one has a Sonos Arc or a Beam 2 connected via earc, then they would most likely be using 1) Stereo or DD+/Atmos formats for streaming apps and 2) LPCM 7.1 or Dolby MAT Atmos for Gaming Console/PC usage. Why would one select 5.1 when they can select 7.1 or Atmos, right?

The only reason I discovered this to begin with is due to a very specific use case where my PS5 (as a bluray player) had to transcode my blurays’ DTS-HD MA 5.1 to LPCM 5.1 so I can enjoy multichannel and lossless playback. Unfortunately, for bluray playback, there is no way to force the PS5 to wrap it in LPCM 7.1 or to transcode to Dolby format instead so I’m guess I’ll be stuck without blurays for awhile. I can only hope that this gets fixed in a future update.

I suppose my final request of you is if you could please get in touch with your technical team and ask them to look once more into it. Even without a PS5, they could very easily test it using a Windows PC (w/c I’m pretty sure they should have) with the steps I’ve outlined above. Should only take 5 minutes to verify. And also, if you could leave the thread open in case somebody experiences the same issue and comes in. Thanks.

Hello fellow Beam 2 / Arc users,

Would like to ask for your help verifying if there are audio dropouts with Multichannel PCM 5.1 post Sonos 14.10 update. The weird issue appears to be for the LPCM 5.1 format ONLY! Even LPCM 7.1 works perfectly. 

If you have a PS5 or even a PC, you could try the steps I’ve outlined on my posts above. Just set your device to output 5.1 channels and if there’s indeed an issue, you should encounter an audio cutout within a minute or two. Make sure that your Sonos app reads the incoming audio format as Multichannel PCM 5.1. Thanks.

Hi @throwawaybeam2 

As per your post in the other thread, Im on 14.10 already and have had my xbox set to uncompressed 5.1 for a while as well, only play games on xbox and have not noticed any dropouts. If I encounter any I will be sure to post here.

Hi, Beam2 user here + PS5 + LG CX. I can confirm the dropouts. I was using Dolby in the PS5 until yesterday since selecting PCM would output multichannel 7.1, even when selecting 5.1 in PS5 settings. This was confirmed to be just a LG CX issue mostly and even though supposedly the channels were correctly downmixed I never bothered to use PCM just in case. An update to LG CX couple of days ago fixed this and now selecting 5.1 in PS5 finally shows Multichannel 5.1 in sonos app. However by doing this you get audio dropouts every 1-2 minutes.

 @ledzep1 

Thanks for responding. I assume you’re on Arc and if so then this could be a Beam 2 only as kikeminchas just came forward with the same issue on the Beam 2.

@kikeminchas

OMG THANK YOU! I didn’t want to to do a full factory reset on my TV (as per Corry P) but I was desperate enough to re-plug/re-register my HDMI devices and do an AV Reset on the TV. Figured this is as close as I can come to refreshing my AV settings without doing a full factory reset. I actually just finished setting up when I saw your response (spoiler - it didn’t work) so it’s truly a welcome surprise. I suppose the CX’s latest firmware update is perfect timing.

From your inputs, we can infer this is probably an issue with the Beam 2 on the 14.10 update. As I was able to use Multichannel PCM 5.1 with no issues before the 14.10 update. Let’s reach out to the Sonos staff and see if they can dig deeper and confirm the issue.

@Corry P 

Hello. As shared above, kikeminchas tested on a PS5 + LG CX + Beam 2 and was easily able to reproduce the Multichannel PCM 5.1 issue. So it’s not an isolated case.

While the sample size is very limited, if we perform a simple process of elimination, it really seems that the Beam 2 on 14.10 is the culprit. kikeminchas tested on a PS5 while I tested not only on a PS5 also a PC. kikeminchas has a CX while I have a C1. Accdg to ledzep1 it works on the Arc and I can confirm that it worked on the Beam 2 prior to the 14.10 update. So all that is left is the Beam 2 running on the 14.10 update.

So again, I would like to ask if Sonos can test for it themselves and confirm if this is indeed an issue or not. This is very easy as in my experience this is reproducible 100% of the time. The engineers don’t even have the wait for very long as the very first dropout occurs with a couple of minutes (and recurs). I have already laid the steps to reproduce the issue. They could test it with a PC which is something they should have on hand.

In my opinion, given that it would literally take 5 minutes for Sonos to test for it, this is the best way to tackle this issue instead of requiring your customer to first perform a factory reset of their TV before moving forward. It is a massive inconvenience, especially if it does not end up solving the issue. I know it’s not exactly what you asked for, but FYI I had just re-plugged/re-registered my HDMI devices and performed an AV Reset on the TV. Figured this is as close as I can come to refreshing my AV settings without actually doing a full factory reset. And issue still remains.

Hi @throwawaybeam2 

As I mentioned, the best way for troubleshooting to move forward is to reset the TV - if this does not resolve the problem, I recommend you get in touch with our technical support team who will create a case for you and be in a better position to assist you, moving forward. 

I have no issues but I don’t have an LG TV. You mentioned an LG update, maybe that’s the reason? It sounds that the update included changes for sound.

@Outburst 

As mentioned, I did an update on my LG TV after I have already discovered and replicated the issue. Pre-TV update, the only thing that changed is literally the Sonos 14.10 update. Post-TV update, issue still persists.

It would be helpful to others if you can share your actual setup. So far what appears to be “confirmed” is the audio dropouts occur ONLY on a Sonos Beam 2 running on 14.10 update while it is receiving the “Multichannel PCM 5.1” audio format. 

@Corry P

Not trying to be rude but do I really have to go through the extra trouble? You were already able to have a colleague look into my diagnostics multiple times. Can’t you simply pass the info off to your technical team?

While I really do appreciate your efforts so far (and I confess I am unaware of the full scope of your responsibilities), it is disappointing from a customer viewpoint to have someone hold your hand allthroughout only to be let go once you’re about to reach the finish line.

I was already able to narrow it down for Sonos and it is very quick and easy to reproduce. It is 100% reproducible. And with a corroboration from another user, it appears to be a legimitate issue. Even as your colleague tried to deflect the blame on the TV, you have to admit that the Sonos 14.10 update is the most logical culprit. To me, this  seems like something that should warrant the attention of Sonos, even without the prodding of their customers.

I may be being dramatic but it is what it is. I believe I’ve done my part as a member of the community. If Sonos does not want to take some initiative, I pass the baton to another troubled Sonos user who is willing to take it from here. I hope it gets fixed in a future update. If not, then this is something to keep in mind. Thank you and goodbye, everyone.

My setup is Beam Gen. 2 → HD Fury Arcana and I tested with a Nvidia Shield and Kodi set to Multichannel PCM 5.1 Tested with. several movies and didn’t have any dropouts. Since kikeminchas also has an LG TV and can reproduce it, but ledzep1 can’t (unsure what TV they use), I’m not sure if it’s really the Beam or the LG TV. Maybe some more people will chime in soon. I reckon if this was a broader issue, we will hear soon. 

I use LG CX (latest 4.40.10 firmware) with sonos ARC not had any dropouts, so could be Beam specific.

If those haven't already tried I would do the good old turn it off and on procedure (TV and Soundbar)

Try a different HDMI lead 

Last resort perhaps try a reset on the TV and sonos.

I have an Apple TV-4HD with LG C9 TV and Arc, surrounds & sub and it’s set to default - to output 5.1 multichannel LPCM.

I played the movie ‘6 underground’ from Netflix for 30 minutes or so, just as a test …and that’s all working okay without any audio dropouts.

What settings do you have set on your c9 for audio?