You know I just had a thought maybe the change is on Sonos' end. Maybe they weren't looking at what sort of Dolby Pro logic type stuff was added to the stereo downmix by the Panasonic 4k Bluray player until some time more recently?

In more recent times I have been a bit surprised how many free to air movies I watch give me surround now even when the Sonos app says it's Stereo PCM

Update: I received a pleasant reply from the Panasonic support team apologizing for the issues and asking for a bit more information including proof of purchase. We’ll see where this leads next.

I got the Arcana today to try and fix the LPCM issue with the Panasonic 820 which it did, however still have the 7.1 bug that Sonos has yet to fix.  However it then caused my nVidia Shield TV to start outputting everything DTS to stereo 2.0 now.  Removed the Arcana and it fixes the Shield back to doing LPCM multichannel so wtf lol.  Also experienced a lot of random CEC issues, unable to control volume and having to power things off and power on in certain orders multiple times etc.  I’d rather listen to some disks in stereo than to deal with those issues so I’m sending it back or selling it.  I sure wish Panasonic or somebody could just fix this issue, especially with all the work ya’ll are doing to pinpoint it, thanks for being persistent and hopefully it pays off!  I too had opened a case with Panasonic and they had also asked for proof of purchase which I gave but then their reply was to go into the settings and set the audio settings to PCM and try etc, things we obviously already tried before contacting anybody so I gave up.

FYI - I have finally listed my no longer needed Arcana as I switched to the DR HDMI 4K to solve my issue. (Scroll back through this thread to see my saga.) Since I was comfortable editing the EDID files. the DR HDMI 4K is a better solution for me.

If you are interested in acquiring my item, the listing is here:

http://ebay.us/MYOBc5?cmpnId=5338273189

It is certainly not a comprehensive solution, but it is a relatively easy one, particularly if your set up is not very complex. Do read the post above for issues with the nVidia devices.

You are a legend Laird. 

I've got all my fingers crossed that you get something back from Panasonic suggesting they accept the problem is theirs and they intend to fix it. 

Thank you!

No news or reply to my providing more info from Panasonic yet though. Fingers crossed indeed.

Acknowledgment but no actions yet:

“Thank you for contacting Panasonic Consumer Support.
With regards to your inquiry, your feedback and observations have been noted and passed along to our dedicated team”
 

Sonos just put a 13.0 firmware release - @GuitarSuperstar - any possibility to confirm if this resolves multichannel PCM 7.1 to 5.1 downmixing issues when playing a DTS 7.1 sound track converted to PCM 7.1.

@madhav I updated the firmware and played the 7.1 audio test on my DTS demo disc… no change. Both side surround channels play the test tone, but both rear surround channels are silent.

Thanks for checking. I guess the firmware fix Sonos were working on according to their CEO for this issue is not a priority.

I returned the Panasonic UB820 unfortunately and replaced it with Samsung UBD-M9700 that I got brand new from eBay and Sony UBP-X800M2
I have two setups

1. Samsung M9700 + Samsung LSP9T projector + Sonos arc ( 2 subs and 2 surrounds) 

DTS audio is RE-encoded on the fly to DD 5.1 so no issues with that. Dolby Atmos is passed through to Sonos arc (TrueHD or DD+).

HDR10+ is supported by M9700 and is supported by LSP9T. No Dolby vision but not a big deal because projector doesn’t support it anyway

2. Sony UBP-X800m2 + LG CX + Sonos arc (1 Sub and 2 surrounds)

DTS gets converted to LPCM 5.1/7.1 - still have to deal with Sonos firmware bug with 7.1 as above.  Dolby is passed through 

Dolby Vision is supported for dynamic HDR. LG CX supports Dolby Vision.

The bug that you are referring to is completely seperate the the post that was originally created, there are several other posts relating to the downmixing issue that cropped up since the LPCM update back in november. I would suggest keeping any posts related to it in a more relavant thread specifically raised about that issue

So I finally got around to putting in a ticket to Panasonic for this issue, and have received a reply which states the following:

“As I am aware, the player can only send the multi channel audio to an audio device connected via the secondary DHMI, Optical or Analogue connections (RCA).

However, I will send your query further to our technical department and will reply to you as soon as I have an answer.”

Can anyone here confirm if they have successfully gotten multichannel PCM out of the UB820 with the AV HDMI, either using an HD Fury or a different TV? I’m pretty sure what the support agent says isn’t true, but I would like someone to confirm that it isn’t true before I get back to them to state as much.

@Surge My UB820 is connected from the HDMI audio/video out port to the HDFury Arcana and I get multichannel PCM audio playing out of the Arc.

I too am also getting 7.1 audio from the 820 through a DR 4K HDMI through my LG to my Sonos Arc. The only time I get 2.0 audio is when the source material is in 2.0 format.

After Panasonic asked for more info on my ticket, they have not further responded.

Hi I'm also getting 7.1 using the arcana. I've noticed today there has been an update on the c9. 5.00.30 not sure if it's anything to do with this though. 

Found this.

https://www.avsforum.com/threads/2019-c9%E2%80%93e9-owners-thread-no-price-talk.3057634/page-879#post-60623628

I’ve got a CX, not sure if there’s an update for me.

Question for the group.

I’ve followed the advice, set DTS to PCM within the UB820, plus set the downmixing to Surround, turned off Secondary audio etc. LG settings as standard.

The ‘Playback Info’ bar within the UB820 is showing DTS-HD MSTR, but within the Sonos app it’s showing as Stero PCM 2.0.

However, I am getting full surround sound across my rear SLs. With dialogue coming purely through the centre Arc. 

What do we think is happening here?

@JamesU2021 That’s interesting. Do you mind posting a screenshot of the Playback Info screen and the title of the movie you are testing?

I believe the Panasonic adds some surround info into the stereo PCM mixes and with the changes for the Arc PCM support they started using I think. Certainly my 4k blurays with DTS tracks seem to get a much better up mix than previously with my Playbase. 

https://en.wikipedia.org/wiki/Dolby_Pro_Logic

This is just a virtual surround, I had the exact same experience as you and documented it earlier in this thread. If your bluray has several audio tracks (like different languages) usually track 1 is English DTS - MA, followed by foreign language tracks in dolby digital 5.1.  Use the audio button on the remote to change the tracks on the fly and you'll very clearly hear the difference between a proper multi channel output and the virtual surround. I used the 4k of Once Upon A Time In Hollywood.

Additionally my LG C9 got the 5.00.30 update and I can confirm that it did not fix any of the hdmi handshake issues with the Panasonic UB820. I'm still getting 2.0 pcm instead of multichannel LPCM when outputing DTS. 

@zad 

Have you set downmix to surround encoded on the Panasonic? Some time after the Arc was updated for better PCM support I put Divergent on and immediately noticed a vastly improved up mix with the DTS-X track with my Playbase. Not quite as good as the Atmos tracks on the sequels admittedly but very good. DTS-HD tracks needed a little bump in volume in the rear surrounds but still much improved. There must be some Pro Logic type of info the Panasonic is adding to the stereo output that Sonos wasn’t looking at previously. I’m not bothered by the lack of DTS support now and will be buying some more 4k release with DTS tracks that I put off buying. I was particularly pleased with 2001. The score sounded much better with the changes being mixed into the rear surrounds.

Ideally people would want to get LPCM rather than PCM for the best result but the TV is probably also a factor in that maybe?

Oh yes I've tried that, I've spent hours trying to find the magic configuration. The issue is an HDMI handshake issue between the Panasonic UB820 and the LGC9, the Panasonic literally won't pass the LPCM signal to the television. I've used other devices that can pass through LPCM / covert DTS to dolby on the fly (xbox) with no issue.

Fake surround is OK, but it's not really the experience that I was expecting from this system. I'm just waiting to get my hands on a Xbox One X, and the Panasonic will go up for sale. It's a fine player but it doesn't work with my system.  And nobody seems to be listening at customer support, we haven't seen a firmware upgrade in 2 years, I don't suspect we'll ever see one.

Hmm i have a Xbox series X and UB820. I certainly wouldn’t be jumping ship to play my movies on the xbox. Have you looked at any of the comparison videos from the likes of John Archer? The UB820 is still one of the best 4K players on the market and there is a considerable difference in image quality over something like an xbox/PS5.

The XSX also can’t and unlikely will be able to play dolby vision from 4K disks for some reason. Which is strange considering that they are moving towards dolby vision being used in games.

The thing is it’s not really fake surround its most likely using the technology Dolby used to put surround information in stereo soundtracks on 35mm film, back in the day, for those theatres that had their technology. Those that didn’t just got a plain stereo playback. The more I think about it the more likely I think it is that Sonos just wasn’t looking at the info in PCM sound that had it until after the Arc came out.