Someone here with the same player had some issues with playing DTS discs.

Try powering down, disconnecting from the tv and reconnecting when the power is on.  Sonos is apparently working on some fixes with lpcm 7.1 channel functionality but it could be a while before something is released.  If your player has a 5.1 output setting option try that as well.

@Paul Tsang I just tested a DTS disc on my Panasonic UHD player with the latest update and the center channel dialog is playing as it should with multichannel PCM 7.1 audio.

Tried . Still didn't work. Not sure what's happening maybe it's the new Sony A90J tv problem 

@Paul Tsang Try unplugging the TV, Arc, and Oppo from power for about a minute and retest.

@GuitarSuperstar  just did. It's the same result. Now even LCPM on the PS5 has the same issue, center channel is outputting on my rear left speaker. Very strange. I didn't have this problem on my previous Sony A9G tv . Dolby 5.1 and Atmos has no issue. Just LPCM

@Paul Tsang It definitely sounds like a problem with your TV and LPCM audio. I would contact Sony if I were you.

Could this be a software problem on the Sonos instead ?

It could be, but from what you have described, I would guess it is probably a problem with your TV. Like I said earlier, I have the latest Sonos software and I am not experiencing this problem from multichannel PCM audio. I even ran a “DTS Sound Check” test from a DTS demo Blu-ray disc and didn’t experience any issues (other than the known 7.1 to 5.1 down mix problem that Sonos is currently working on). If it were strictly a Sonos software problem, we would be seeing many more people reporting the issue.

@GuitarSuperstar that's what I think too. I just contacted Sony support they said to try changing the HDMI cable but I doubt they know what they doing. If other audio decode is working why would it be a cable problem

I'm going to try factory reset the tv and try switching to the HDMI cable that sonos arc came with it and hope for the best . 

Hmmm

I too am having the same problem with an A90J.  Any LPCM content from my Plex server playback through any device attached to the TV, is sending the Front Left and Right channels to the Rear speakers and playing rear channels on the soundbar.  DD and Atmos are fine, but sadly anything with DTS or even 5.1AAC is causing the issue for me.

If i Turn eArc off the problem goes away, re-enabling eArc it returns.  I could've swore for a few days everything was fine then this started happening and I’m about to try some factory resets myself to see if I can get it back in working order

I just chatted with Sonos support on this after performing a factory reset and still having the problem, sadly they have no known issues regarding the A90J and LPCM audio playback issues and said I’d have to call in to be escalated to level 2 to continue more troubleshooting. 

FlatpanelHd already informed sony and they are aware of the issue and will provide a firmware fix. Not sure when but it will come. They admitted EARC is bugged. So it's not Sonos problem . 

Interesting when I called Sony they blamed Sonos.  Glad to see someone got them to look into this. 

I am hving the same issue with my new X90J as well! Turn off the eARC mode the issue goes aways (but DD 5.1+ instead of PCM 5.1 or 7.1), and comes back after re-enabling the eARC mode(show up PCM 5.1 or 7.1 in app), then he center vocal voice just outputs from the rear surround!  

I've  encountered this before. This is caused by your TV passing through LPCM in 7.1 format instead of 5.1 format. Currently downmixing doesn't work on the ARC, pending a future fix, so anytime your TV passes 7.1 audio to the ARC it will mess up your surround channel audio 

The actual is any non-Dolby Atmos DD5.1 will output as PCM 5.1/7.1 and mess up the surrund channel, I tested below:

(Apple TV 4K, Sony X90J eARC mode ON and with April update patch, Infuse 7 Pro player)

Dolby Digital 5.1/7.1 = PCM 5.1/7.1 = mess up 

Dolby Atmos TrueHD 7.1 = PCM 7.1 mess up

DTS = PCM 5.1/7.1 = mess up

ETC...

I got exactly the same issue with my a80j. After I set it to Dolby 5.1 then it is fine. So it is sonos's issue then.

does anyone have the TV except sony J (2021)series？

Confirmed. I have the same problem on my brand new A90J.

Hopefully their correspondence with FlatpanelHd was not a canned response, and is indeed something they plan on fixing soon. I worry, as they have seemingly dropped the ball recently on promised/working features.

I have the same problem - Sony A80J Bravia TV. When the audio format is LPCM 5.1 (per the Sonos App), the audio that should go to the center channel plays out of the left surround. As pointed out earlier on this thread, it only happens when eARC is enabled. The bummer is that I’d really like to enable eARC, because that’s how I get Dolby *Vision* (in my case from the new Apple TV 4K). I also verified the problem with two sources (the Apple TV, and a Blu-ray player that converts DTS to multi-channel LPCM) so figured it had to be either the Sonos or the TV. Based on this thread, seems like it’s the TV. Really hope Sony fixes it soon    Also wish I’d found this thread before beating my head on the wall for several hours, but at least it makes sense now :-)

GOOD NEWS to everyone, today Sony released a new firmware and it fixed all the LPCM problem that I had the last past months, sound is outputting at the correct channels when movies playing in LPCM.

Everyone please give it a try!

Good news, is this issue on LG as well?

Perhaps LG can get there act together and release some fixes, I thought this was a Sonos issue though?