You answered your own question the Sony is converting the stream to PCM which the Beam can handle over HDMI. The problem would be over optical.

It’s a function of HDMI CEC. The Sonos reports two things to the hub, your TV, one is that it is a speaker, and the other that it handles two codecs, stereo and Dolby Digital. The HDMI CEC hub in the TV then sends the acceptable codecs to all source devices. Assuming the source device is HDMI CEC compliant, it then adjusts itself to only send a Dolby Digital or stereo signal along to the hub, which then forwards that to the speaker. 

There are some devices that can accept an HDMI CEC command even when the option isn’t available in the options shown to the user in the audio settings for the device. 

Unfortunately, there are some hubs (TVs) and sources that either didn’t properly implement HDMI CEC, at least in the first attempt, which is why you frequently see suggestions for people to download new software for the TV, as well as a reboot process in case something has gone awry. Unfortunately, chances of software updates tend to be slimmer on source devices, but these updates should be applied where possible.

Unfortunately, it’s frequently the receiver/speaker that gets the blame, when it is most often something upstream. To my knowledge, to date, Sonos has not needed to update their relatively tangential implementation of HDMI CEC. It has almost always been an implementation issue in the HDMI CEC hub, built in to the TV set. There have been a handful of issues with source devices, but since that’s significantly upstream from the Sonos, it’s really much harder to define from the end point, the Sonos. 

Thanks both of you.   So, I think you’re saying that my player, the Sony UBP-X800 Mk2, converts DTS to Dolby Digital on the fly?  If so, this is good news, and I will share this news with others via the BD Players thread. 
 

I appreciate that the player’s ability to do this is only one (necessary) link in the chain, and that as you say, Bruce, the Sony’s HDMI-CEC (aka Bravia Link) implementation ensures that the Beam’s desire for DD 5.1 reaches the player. 

No, I wouldn’t expect this is on the fly conversion, I would think the HDMI CEC link is telling the player to only play the Dolby Digital track. But that’s a guess, you’d need to check with the folks at Sony for more clarity. On the fly conversion is a whole different set of electronic circuitry of some cost, and is rather unlikely to be included in the player, without heralding it and using it as a marketing point. 

There would be a way to test this, with relatively little complexity. Find. Blu-ray Disc that does not have a Dolby Digital track, only stereo and DTS and play that. See what shows up in the controller for your Beam. If it’s stereo, then your Blu-ray isn’t doing on the fly translation. If it’s Dolby Digital, then it is doing the magical translation,  and I need to go buy one. ;) 

Or possibly, the TV is doing the translation, since it’s in the stream. Unlikely, but not impossible. 

Sorry, I didn’t make that point clear in my original post:  all of my test discs had NO Dolby Digital English language soundtracks on them (and that includes DD5.1, True HD, Atmos, etc).  If they had, I would have selected one of those soundtracks from the disc menu and would never have discovered my surprising finding!   And my French, German, Potuguese and Catalan etc isn’t good enough to watch in any other language than English.   So I select the DTS tracks from the disc menu, and it plays as DD5.1 on the Beam, just so long as I set Digital Audio Output = PCM on the BD player.  Magic!

Regarding the TV, I haven’t seen anything in the manual or settings menus to suggest it’s doing any sort of audio conversion.  But someone might know different?

BTW, I got the BD player model name wrong in my first post:  its the Sony UBP-X800 M2 (as in Mark 2; I’ve seen others with the original X800 complaining of no joy with DTS...) 

That is indeed magic!

Now I need to go price the UBP-X800 M2. Thanks for sharing!

You can verify the audio format that SONOS is receiving by going to Settings → System → About My System

Hi Buzz, you’re right, I did that as per my original post:

• Sonos app reports Beam is receiving “Dolby Digital 5.1”

Bruce: I paid £265 for it in the UK. It’s a great player - superb picture and they seem to have ironed out some quirks/issues from the Mak 1 version. Very limited on streaming apps and other bells and whistles, and some won’t like the minimalist styling and lack of a display, but I love it. Super quiet too, even with 4K discs. 

Hi, did you try to connect the BD player HDMI audio output directly to the Beam ?

Just to be sure the TV is not doing anything in your setup 

Curious that a player configured to send PCM decides actually to use DD

Maybe you can although try to disconnect the Beam and see what signal is sent to the TV, 

My best guess… BRP is outputting PCM 5.1 and TV is transcoding to DD5.1.

This would be very good news!

Yes, if you have that BRP and TV.  And if I am correct,  which  is far from certain. 

A couple of years ago I stopped buying discs, in favor of my Apple TV. That may change, if this device does what it seems to. It’s at Amazon for $248 here in the US. 

But I’m going to hold off until I get the Arc at the earliest, and see how things stand. Changing back from one format to another is a pretty big change, and I’ve gotten used to not having physical media. 

I had the same issue on my LG C9. Had to enable PCM for DTS. Dolby Digital discs played with no issue under bitstream. I have a Panasonic DP-UB820. Glad I got it working but it’s clearly a codec support issue with Sonos. For the premium, DTS could be supported too. 

@alexfirth91 Did you get surround sound or just stereo?

I only tried one film, but Jojo Rabbit worked in 5.1 surround DTS as selected. When I first tried I heard nothing, but the fix I did worked. 

@alexfirth91 did you change the settings on the TV or on the Blu-ray player? I also have a C9 and a Panasonic 820, and when I play a DTS Blu-Ray I get silence. I have been able to work around it by using my Xbox, but that defeats the purpose of why I bought the Panasonic. Seems I have to choose between Dolby vision or DTS until Sonos does a firmware update.

You should be able to at least get stereo out of the 820 with DTS tracks. I have the 420 and get stereo on my Playbase. If you're lucky maybe you can get multi channel pcm as well. I'm hoping people will find that the case with new TVs and the Arc.

I changed the settings on the player. I’ll post exactly what I did. 
 

Dynamic Range Compression: Auto

Optical down sampling: up to 192kHz

Downmix: Surround encoded

HDMI output settings of music playback: normal
 

Digital Audio Output: Dolby Audio = Bitstream 

DTS/DTS-HD = PCM 

BD-Secondary Audio = off

For the High Clarity Sound settings: output selection of video playback : Audio Output = Auto

Output selection of audio playback = auto

I also have in the main audio settings “Analog Audio Output” = Off

The fact you have a Sony TV and player most likely helps. All three devices are talking to each other would be my guess and sorting out the issue.

With my setup I had the player setup wrong but the TV and player gave me stereo on my Playbase anyway. Didn't realise until I looked into all the details of how these things work.

I’m late to the party on this one, but perhaps my experience may be of use…

I recently bought a Sonos Beam (fell prey to Black Friday temptation!), having read and watched quite a few reviews that sang its praises.

But none of them mentioned the lack of DTS compatibility, and I didn’t think to check up on it before buying.

So with my Samsung 4K TV and Sony X700 4K UHD player, Dolby Digital was working through the Beam but DTS audio didn’t.

I found this thread while searching for an answer. Anyway, having read that some older Blu-ray players can convert DTS to Dolby Digital, I remembered I still had my old Sony BDP-S3700 Blu-ray player, which I used prior to buying the X-700 4K player.

So I dug it out and connected it up to the TV, and delved into its menu (System Settings/ Audio Settings / Dolby D Compatible Out) and enabled the DTS-Dolby conversion, and hey presto it works - the Sonos app now reports that the Beam is receiving a Dolby Digital 5.1 signal!

So, if you have a collection of Blu-ray disks that only have DTS audio and would like to get surround sound off them, it could be worth hunting down a used or refurbished BDP-S3700 on eBay.

Mine is a unit that’s been region-hacked by a company in Croydon, UK, so I can also play region-coded BD and DVD disks from the US, of which I have a collection.

At the time of writing, the company I bought mine from are still selling them, for £149:

https://www.ebay.co.uk/itm/Sony-BDP-S3700-WiFi-MULTI-REGION-ALL-REGIONS-Free-ABC-DVD-1-8-Blu-Ray-Player-Nb/274571111098?hash=item3fedb6aaba:g:q0YAAOSw6Spe2n-F

As my Samsung TV only has two HDMI inputs (one of which is used for the Sonos Beam) I just have to swap the HDMI cable between the two players when I want to watch a DTS Blu-ray disk - not too big a deal.

Hope that helps somebody!

Very curious to find this thread, all my research thus far has indicated that Beam can only output stereo PCM from players that do not convert DTS on the fly ie: Xbox Series X, PS5 or the old Samsung/Oppo Players.

Have an LG B9 and am every interested in investing in either the Sony UBP-M800 Mk2 or the Panasonic DP-UB820 but was worried about missing out on 5.1 for all DTS based discs.

Can anyone confirm that similar results could be achieved with the B9? @alexfirth91@Withanee have you experienced any inconsistencies/issues since?

If it’s a matter of changing audio settings on the players Sonos needs to start communicating this ASAP, as the rest of the internet is under the assumption there is no hope for consistent 5.1 across all discs with the Beam.

Thanks!

After investing in a Beam and 2*SLs on the black Friday deal to go with my new Sony 55HX9505 I became one of the large number of people to find themselves very disappointed not to be able to enjoy surround sound from my BD collection. My Sony (non-4k) BD player could output sound in PCM so at least I could get Dolby Digital 2.0 with which the Beam did attempt to produce some surround content but which wasn’t terribly convincing.

I’ve decided to upgrade by BD player to a Sony UBP-X800 M2 and after two small adjustments on the sound settings I can confirm I am getting Dolby 5.1 on the 3 discs I have tried so far - LeMans 66 (7.1 soundtrack), Apollo 11 (DTS soundtrack) and Master and Commander (DTS Soundtrack).

Settings here: 

As a result of this purchase (£280 from Amazon.co.uk - prices seems to be creeping up post Brexit) I am a very happy. Hope this information helps others who find themselves in a similar position to myself.