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.

Corry P 1 year ago

Hi @throwawaybeam2 et al

We now recommend you reach out to the TV manufacturer (LG) as this behaviour is also occurring with different soundbar manufacturers (so it’s not a Sonos-specific issue).

Alternatively, please utilize different audio formats from McLPCM 5.1 (e.g., McLPCM 7.1, DD+, etc).

I hope this helps.

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Userlevel 2
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Update to this - For the last week, I’ve been using the cable recommended in in this thread and so far it’s been perfect. I will re post if I start having issues.

I finally found this thread after I’ve already had Apple replace my Apple TV (2022). I had a week where I thought the issue was fixed, but it was just luck since the problem is very intermittent for me. After that I finally suspected my LG C2 or the Beam Gen 2, since the issue before exclusively occurred on a single Apple TV.

Really disappointing there is no official fix for this, especially when the Arc is supposed to be fine.

Userlevel 3
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478 replies and Sonos hasn’t even acknowledged an issue. 

Userlevel 3
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478 replies and Sonos hasn’t even acknowledged an issue. 

Given how they’re currently going through a courageously disastrous new app rollout, that’s no surprise. They don’t care even if they screw over most of their users.

TLDR of the thread for prospective buyers who find their way here: If you own an LG TV, do not buy this product! The same issue does not exist for the Sonos Arc so it is likely a Sonos issue. However, it’s been 2 years since this thread and Sonos has done nothing (except wash their hands off of the issue).

Wish I'd found this thread before buying. LG G3 with Apple TV 4K. Beam 2. PCM 5.1 dropouts.

 It's going back to Amazon this week.


First Sonos purchase, horrible experience. Further to comments already made in this thread...I don't see how I could buy another Sonos product in good conscience given (1) the ramifications of this issue in the future, i.e. products suddenly become unusable following firmware updates and (2) the dismissive manner in which this has apparently been addressed. I loved the sound initially and was even thinking about buying more Sonos products, but nope.