Multichannel PCM 5.1 dropping out since 14.10 update


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Anyone else experiencing the same issue? Multichannel PCM 5.1 blanks out for a second every 1-2 minutes. I don’t think it’s a bandwidth issue as it works flawlessly with Multichannel PCM 7.1 (thorough test) and Dolby TrueHD Atmos (quick test). And it may have been caused by the Sonos 14.10 update. Setup is PS5→ LG C1→ Beam 2 (via earc).

 

2 weeks ago before the 14.10 update, I watched a bluray film wherein I had my PS5 transcode the DTS-HD MA 5.1 audio to Multichannel PCM 5.1 (as the C1 does not support DTS) and had no issues. Earlier today, I played a bluray film for the first time in 2 weeks and I encountered consistent audio dropouts every 1-2 minutes. It had the same setup where DTS-HD MA 5.1 → Multichannel PCM 5.1. I tested other bluray discs including the one I watched 2 weeks ago and they all now have the same issue.

 

Curiously, I’ve been gaming heavily on my PS5 the past two 2 weeks and haven’t had any audio issues. Then I realized that I’ve been using Multichannel PCM 7.1 when gaming on my PS5. So I made some changes under the PS5 sound settings to make it output Multichannel PCM 5.1 instead. Lo and behold, I am now getting the same consistent dropouts in games and even on the PS5 main menu.

 

I think it’s due to the Sonos 14.10 update as that’s the only firmware update I’ve done in the last 2 weeks. No PS5 update, no LG C1 update. Well actually while I was composing this post, I received and applied the latest LG C1 firmware update and I still have the same issue.


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Okay, so I fix it by myself. It wasn’t a Sonos issue but an LG issue. I saw that a lot of people with that issue own an LG TV. So I look for more information on that. I found an issue on Reddit link to 5.1.

What I did on my LG C1

  • Remove my Sonos Beam from the external output as a sound bar
  • Reconfigure Sonos Beam as a sound bar (Sonos is not directly proposed by LG you have to enter the brand in the search bar)
  • Uncheck one of the conditions of use to reboot of my LG. 

Since I don’t have issues anymore and that without reset!

WebOS version: 03.33.11

Sonos version: 14.18

Can you tell me how to do the first two steps please, can’t seem to figure it out :/ help would be appreciated! 

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On the main page I go to param of (input/ouput)

And I got settings screen: 

 

On the main page I go to param of (input/ouput)

And I got settings screen: 

 

Thank you for taking the time to show, it’s greatly appreciated. All done and I’ll test it tomorrow! :)

@Fskies Really awesome! Followed the steps you indicated and the problem is solved for the moment (fingers crossed!). Thank you very much for sharing!

I’ve been having this same issue (audio cuts out for 1 second every 1-2 minutes) the past few months with my set up: LG C1, PS5, Sonos Beam gen 2 + One surrounds (with all the OEM cables). Configured with eARC/bitstream/pass through on the C1, AV receiver 5.1 linear PCM on PS5. It’s really been maddening. I usually unplug/replug everything and toggle all the settings for a few hours and then it’ll go away, and come back in a month 🤦‍♂️ Please fix this Sonos…

 

Looks like this go round, toggling TV sound share on and off in the TV’s settings as someone previously suggested broke the curse. Will try this first going forward

I’ve been having this same issue (audio cuts out for 1 second every 1-2 minutes) the past few months with my set up: LG C1, PS5, Sonos Beam gen 2 + One surrounds (with all the OEM cables). Configured with eARC/bitstream/pass through on the C1, AV receiver 5.1 linear PCM on PS5. It’s really been maddening. I usually unplug/replug everything and toggle all the settings for a few hours and then it’ll go away, and come back in a month 🤦‍♂️ Please fix this Sonos…

 

Looks like this go round, toggling TV sound share on and off in the TV’s settings as someone previously suggested broke the curse. Will try this first going forward

Spoke too soon… issue is back this morning and toggling the tv sound share setting isn’t resolving it…

Spoke too soon… issue is back this morning and toggling the tv sound share setting isn’t resolving it…

What else is connected to the TV HDMI ports? Have you switched off CEC on those ‘other’ connected devices to see if that solves the issue?

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  • Remove my Sonos Beam from the external output as a sound bar
  • Reconfigure Sonos Beam as a sound bar (Sonos is not directly proposed by LG you have to enter the brand in the search bar)
  • Uncheck one of the conditions of use to reboot of my LG. 

Would be interesting to understand the theory of how this helps, I find this area of WebOS quite mysterious and not sure what it manipulates, CEC command set I suppose but I don’t understand why it needs to know the make/model of the sound bar to do that. I’d also have thought that my C1 factory reset would have covered this step, but it didn’t seem to help in my case, maybe some reset commands are sent during the first step (I don’t know if such things exist in CEC).

On the plus side, I dismantled my setup for a week and there have been no drops for several hours today after I reconnected it.

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I’m having the same problem. I recently upgraded to the new Apple TV 4K which fixed the problem of everything being sent as PCM 7.1 but now with PCM 5.1 I’m getting audio drop outs every minute or so. I’ve tried all the fixes in this thread to no avail.


I’ve done a diagnostic that should capture the issue so hoping to get some feedback if possible @Corry P 

Diagnostic 1711446570

Hi all,

I’m having the same issues.

I’ve recently bought a Sony UBP-X700 4k Blu ray player. Up until now I’ve been using my PS5 but wanted to take advantage of the Dolby Vision and better quality from a 4K player.

However, any 4K disc that doesn’t output Dolby Atmos seems to have issues. It outputs the audio as Multichannel PCM 5.1 but every 20-30 seconds I get a momentary drop out of audio and sometimes no audio output at all. As I said Dolby Atmos plays fine.

My setup:

TV: LG C1

Sonos Beam 2

2x Ones as surround

Sub Gen 3

I had similar issues when first trying 4k discs on my PS5 but I bought a better HDMI cable and this seemed to fix the issue. I’ve done the same this time to no avail.

Any help would be greatly appreciated or if a fix is known.

thanks

On the main page I go to param of (input/ouput)

And I got settings screen: 

 

Was really hoping this would work, and initially the first try did work. Tried it again today and back to no audio coming through. Has anyone had any success or identified a fix?

This issue is so widespread on sonos reddit  and here that i cannot recommend buying sonos if u have a ps5 and lg tv. The bug has been around for 6 months. I too have this issue and none of the fixes will stop the dropouts.

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I also noticed a lot of discussions elsewhere. I have got another support call scheduled tomorrow and if I just get told to unplug and re plug again etc I’ll be tempted to try and get a refund under UK law. I had a playbar which was flawless but eARC has clearly been rushed and Sonos do not seem particularly bothered to try and use the resource of this community to resolve the issues 

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Quick update, support call did not help, told it was a WiFi issue despite the beam being hardwired and the only Sonos product on my network. Was also told to do a factory reset but I’m reluctant to do that as Sonos seem to generally discourage that. 
 

Can we please get some acknowledgement from a Sonos staff member to help escalate this as it is making my system unusable as most content is PCM 5.1.

It’s really bad and just makes our products unusable. Does anyone know if Sonos are looking at this issue a whole which may be fixed in upcoming updates? As it appears to be happening to a lot of people.

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@Corry P is at least aware of the issue (look at first page of this thread) but no idea if this is really actually being looked at by engineers. It seems that they won't check it out without factory resetting TV and Sonos. I cannot do that because I would lose trueplay and I don't have easy access to an iPhone. Others in the thread refused to factory reset for different reasons so I am afraid we are stuck, stupid really...

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What I did on my LG C1

  • Remove my Sonos Beam from the external output as a sound bar
  • Reconfigure Sonos Beam as a sound bar (Sonos is not directly proposed by LG you have to enter the brand in the search bar)

My drop outs returned today, about 59 seconds apart. I tried the above steps, made no difference. Maybe we have similar but different problems.

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@Corry P is at least aware of the issue (look at first page of this thread) but no idea if this is really actually being looked at by engineers.

I’m pretty sure this is not being looked at by Sonos given the chat conversation I’ve had with support

Quick update, support call did not help, told it was a WiFi issue despite the beam being hardwired and the only Sonos product on my network. Was also told to do a factory reset but I’m reluctant to do that as Sonos seem to generally discourage that. 

It seems that they won't check it out without factory resetting TV and Sonos. I cannot do that because I would lose trueplay and I don't have easy access to an iPhone. Others in the thread refused to factory reset for different reasons so I am afraid we are stuck, stupid really...

Factory reset of the TV was originally requested in the thread which is much more inconvenient than resetting the Sonos, but I eventually did it and there was no change to the drop outs. Now my drop outs have returned I’ve also factory reset the Beam (which seems to be the new request from support). Now on Sonos 14.19 (LG still on 03.33.11), but the factory reset of the Beam did not resolve the drop outs, so I’ve submitted diagnostics 403846833 to capture.

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@Corry P any chance of another look at this? Every step seems to have been exhausted in terms of resetting and re plugging.

I have been through every option I can find trying to isolate a cause but nothing fixes it. I measure my dropouts about 40s apart but sometimes a bit longer, completely repeatable. I took this diagnostic after about 5 or 6 dropouts in a row. Would be happy to do any more tests with support if required, thanks.

Diagnostic 1814488426

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Hi guys, same here the issue is back ☹️

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Hi @kikeminchas, @ste_ms et al

If a factory reset of your LG TV does not help, I can only recommend you get in touch with our technical support team who can, at least, create a case and get things documented - if nothing is documented, there isn’t any evidence that there is a problem and it will therefore not be investigated.

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@Corry P just checking but if we’ve already been on to support do we already have a case or is there another process to follow?

Also
​​​​​@RANDUSR23296 has already raised a case as have others possibly, can you confirm if they are being looked at?

 

You mentioned trying to reproduce the issue in an earlier post and then replied saying it was a CEC issue so presumably you were able to reproduce the problem and so maybe are already in a position to identify a fix or at least confirm it as an LG issue?

Thanks

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Hi @ste_ms 

@Corry P just checking but if we’ve already been on to support do we already have a case or is there another process to follow?

If you’ve already been in touch, you will have an existing case. Certainly if you received an email afterwards.

Also
​​​​​@RANDUSR23296 has already raised a case as have others possibly, can you confirm if they are being looked at?

I can tell you nothing about someone else’s case.

You mentioned trying to reproduce the issue in an earlier post and then replied saying it was a CEC issue so presumably you were able to reproduce the problem and so maybe are already in a position to identify a fix or at least confirm it as an LG issue?

Not really. My colleague spotted something in the logs and recommended a TV reset. That customer refused to reset their TV and stopped replying - nothing came of it. I don’t think we’ve reproduced anything.

Sorry I can’t be of more help.

 

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So after an inordinate amount of time and effort trying to solve this I think I might have fixed it with…a new HDMI cable

after trying every variation of settings, resets, earc on/off, and cable testing through the Apple TV (which reported no issue) I tested my PS5 with 5.1 (as reported it defaults to 7.1 in soundbar mode and this worked fine) and did not have the same issue. I then swapped the cables between PS5 and ATV and seemingly no more dropouts on the ATV.

I’m absolutely baffled how the cable can carry Atmos, 7.1 fine but couldn’t do 5.1 - I wonder if a certain pin in the cable is in use that otherwise isn’t with other sound formats?

 

I need to keep testing as it may come back but for now I wanted to let people know in case I can save them the same frustration I’ve had the last few weeks.

 

 

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Hi @ste_ms 

Thanks for updating the thread!

That is baffling - as both formats are McLPCM, they both need the additional bandwidth of eARC, so it seems strange indeed that a cable change would permit 5.1 to work when 7.1 already did.

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