PS4 Pro outputting PCM via LG CX shows Multichannel PCM 7.1 for Sonos Arc, but rear surrounds have no audio

This is not true when playing games on the PS5.

I have no streaming apps installed so I cannot test streaming audio. 

My PS5 still sends 5.1 when set to AVR and reducing the channels from 7.1 to  5.1.

When the system is set to "sound bar" it sends the 7.1 LPCM. The surrounds output sound like normal. But no 5.1 downmixing from Sonos yet.

LG settings Digital sound passthrough, eArc On, HDMI output Bitstream. (Setting to PCM gives stereo sound says the Sonos app)

What’s the news on any update to fix this issue?

Was it this month we were potentially getting a update to fix it, I get they like to test things but it seems to be taking for ever.

Waiting on this update as well. I hate having to turn on/off passthrough to get proper audio output for non atmos content

Hi @ledzep1 & @Shadylane 

At present, we have no time scale to share, I’m afraid.

Hi

Was this fixed in recent 13.2 update?

Release notes don’t give any useful information, and I have seen a few mention this firmware has sorted the issue, can you confirm please.

Thanks

Hi @ledzep1 

This has not yet been addressed. I too have seen mention that it seems to have improved - I don’t see why this would be the case (wishful thinking?).

As it counts as a new feature, rather than a bug fix, I would suggest that it will be specifically mentioned in the release notes, when it does arrive.

Wow, this is taking a long time to fix. You would think this is trivial since downmixing is something that has been around for a long time. Should be not really a problem for a company that has, I suspect,  lots of audio experts. Don’t get me wrong. I’m heavily invested in Sonos, and I have no other choice than to wait. I’m just really surprised this was even missed in the first placed when launching the Arc. 

I couldn’t have said it better myself. And I believe it was said that a fix would be anticipated this past July. A shame. I love my speakers; but I expect better.

Add my name to the plate, I’m really excited about a proper downmix from LPCM 7.1 to LPCM 5.1. I’m not angry or anything, but man…my 4K library is only half loved right now. This would certainly get me on board for some new speakers for other purposes :)

Same problem with

Sonos Beam gen 2

LG G1

we get multichannel 7.1 instead of 5.1 in pass through mode

Hi everyone, just purchased the Beam Gen 2 today and I came across a similar issue with: 

Sonos Beam Gen 2

LG C9

PS5

PS5 set to “soundbar” and LPCM.

TV set to “bitstream”, “passthrough” (setting “auto” will downgrade to stereo PCM).

Sonos app reports Multichannel PCM 7.1 despite the Sonos Beam only being 5.1(clearly Sonos bug).

Connection to TV using eARC.

If I select “audio receiver” instead of soundbar in the PS5 menu, I can force the PS5 to 5.1 channels, then the Sonos app reports Multichannel PCM 5.1 correctly. I don't know whether using the “receiver” option vs the "soundbar” option is a good fix since it asks me to map the locations of the speakers in the room which I don't have (being a soundbar), so I'm afraid the sounds I'll get will be inaccurate. But selecting “soundbar” sets it automatically to 7.1, indicating that somehow the Beam tells the TV incorrectly that it supports 7.1 and thus the PS5 defaults to it with no option to change it.

@Corry P is the discussed fix going to solve my issue as well? I have seen people here mostly talk about the ARC but I use the Beam. The issue sounds identical to what the Arc users experience though. Also is there some kind of update or some estimate for a fix? Is it still being worked on (since this thread seems quite old).

Thanks!

Another new Arc owner here with a 5.1 setup, and an LGC1 having this issue. 

I’m kind of amazed scrolling back how long this has gone on without a fix. Somewhat disheartening. 

Right? I really hope they won't let it die… it's a significant issue for many people…

I hoped they fixed it with the recent update but they didn't :(

What happened to this issue and supposed fix sonos support?

I’m sure there was talk that a fix was in the works, sounds like that was nonsense. If a fix was in the works it would not be taking this long.

Anyone from Sonos care to update?

Lgc1 does not support dts pass through 

Only c9 or older does

Also the newer lg TVs have this problem with games waiting on a firmware fix

There's a video on YouTube by hdtv test detailing most of the issues in this thread 

I am sure this has already been mentioned, but the Apple TV is also receiving the same issue with the audio being interpreted as Multichannel 7.1; just like my PS5. I did not have this issue with my Chromecast w/ Google TV. 

You would think after the CEO tweeted about a fix being in the works during this past summer, that it would be here now. I have no idea what Sonos is doing.

It’s crazy to me that LG hasn’t even acknowledged this issue. My guess is, they’d rather just sonos down mix the signal and not have to do anything. Do you know which HDTV video it was where he highlighted these issues?

I’m really bummed to see that technology in 2021 continues to not play nice together. I appreciate sonos trying to solve this problem by offering downmixing but LG should be the ones to blame here imo. I just purchased the C1 and I absolutely love this TV and my arc setup but it’s disheartening seeing this issue. 
 

@Corry P is there any update to this with regard to the feature being worked on? I understand there might not a release window yet but it’d be nice to get confirmation that this is something that is still being worked on, considering more buyers will be picking up TVs like the C1 over the holidays. Thanks. 

Perhaps its not an issue as such, and just how the lg and sonos arc report everything in LPCM as 7.1.

I must admit when the sonos arc reports something as multichannel pcm 7.1 it sounds fine to me.

i don’t have any rears though, just the ARC and Sub here.

In any case It would be nice if someone from support could respond, as much as I love sonos, I think their communication could be a lot better.

Well, Sonos already admitted it’s an issue. It is very noticeable when you have rear speakers. Just hope it doesn’t take as long as adding DTS support to fix this *wink*

I have a similar issue but not sure is the same? Got a Beam 2 , LG CX and nvidia shield. When playing a dolby file in Plex i get the correct codec ie: AC3 , i get Dolby Plus in the app, TrueHD, i get Atmos... Plex is set to Passthrough. However, when i play a dts file, i get this Multichannel 7.1. strange thing is that plex is not even transcoding the Audio, it's doing direct play. How is that even possible since my TV does not support dts? I hear sound from the rear speakers but I assume is wrong then?

Hey that’s what I’m wondering too…why is the shield doing that as multichannel 7.1….no idea 

I have a similar issue. I just changed from a beam to a beam gen2. I am using an Apple TV as source with an lg cx tv. When using the earc connection and digital out passthrough on the tv I get multichannel pcm 7.1 whenever I play any dolby 5.1 on the Apple TV. Changing the digital out to auto it changes the signal to Dolby Multichannel PCM 5.1. A similar thing happens on the ps4 using pcm. I feel like the lg cx is telling source devices to send multichannel pcm 7.1 instead of multichannel pcm 5.1.

Passthrough is exactly what it sounds like, the audio is “passed through” the TV exactly as it comes from the source.  So if the source is 7.1, you get 7.1.