LG C9 + Arc + UB820 / Multichannel PCM for DTS Blu-Ray discs

Some are getting it to work. Maybe set the Bluray player to bitstream and let all the devices sort it out.

https://en.community.sonos.com/home-theater-228993/lpcm-and-4k-blu-ray-players-6850675?postid=16488025#post16488025

I’ve got the same setup. Can’t get it to work either for DTS blurays. Have run out of settings to try on 820 and C9. Nintendo switch and PS4 gaming is fine and outputs LPCM 5.1/7.1. 

Same for me. I have a LG C9 and Sonos Arc with 2 one sls. I can get multi channel from my PC, PS4 and PS5; I set the the Sonos Arc to Passthrough, the devices to LPCM and the app shows that I amn receivng 5.1 channels. However. my Panasonic UB820 shows as PCM stereo when I set the DTS to PCM. I’ve tried leaving everything unplugged overnight and tried other settings but no joy.    

I also have the same setup. Instead of losing more hair, I finally gave up and purchased the Sony UBPX700, which also has Dolby Atmos and Dolby Vision.  It’s very inexpensive and it works. I am now getting LPCM 5.1/7.1 when playing DTS discs.  Until the issue is fixed, I will use the Panasonic for Dolby encoded discs and the Sony for DTS encoded discs.

I think I found the solution.  The player and the Sonos app are showing 2 channel, but I’m getting surround.  Try it and let me know your thoughts.

My set up:

TV: LG C9 

Player: Panasonic UB820

Sonos: Arc, Gen 3 Sub, One SL x 2

Audio settings on the UB820

Digital Audio Output - DTS: PCM

Downmix: Surround Encoded

Audio Settings on LGC9

HDMI ARC

Digital Sound: Passthrough 

eARC: On

One thing to check is what type of DTS track you are trying to play. I was checking the 420 specs and it can't decode DTS:X only bitstream it. It can decode DTS-HD tracks. The 820 will be same I'd expect.

I have a LG CX with Sonos arc and 2 ones as surround and a UB820

Watching Tenet last night I couldn’t get anything other than 2.0 to show on the Sonos app despite fiddling with the Panasonic and LG settings (connected via eArc) so infuriating. I had some sound coming from surrounds but all dialogue from the arc so I assume this was 2.0 

Have you set the DTS setting on the UB820 to PCM?

Yep tried both still shows stereo pcm 2.0 on the app 

DTS must be set to PCM. Also, try turning off Secondary Audio.

Set your TV to these settings:

1. Turn on SIMPLINK. This can be done by:
   1. Following the directions during your TV’s first-time setup process.
   2. Heading to All Settings -> Connection -> Device Connection Settings
2. Change your Sound Out to HDMI ARC
3. Go to All Settings -> Sound -> Additional Settings and turn on eARC.
4. Under All Settings -> Sound -> Additional Settings -> Digital Sound Out select “Pass Through”