Hello ​@Roger.S, welcome to the Sonos Community!

MKV files are not an audio format. A lot of bandwidth would be used up with all the video getting transported, only for it to be thrown away in the end.

Due to the issues this would cause, it is very unlikely that we will ever support video formats in a Music Library.

You can play a MKV file on your TV and have your Sonos Home Theater product play the audio from it as a workaround.
I hope this helps.

Hi Thanks for the reply, maybe I didn't explain properly what I was trying to do.

I just want to play ripped TrueHd music in Dolby Atmos from my external library.  Due to limitations the mp4 container cannot support TruHD, mkv and mka are supported. You can just put TrueHD audio in mkv, this is what is supported in all Blue-ray Audio disks

I can play Blue-ray audio disks in ThueHD and Atmos from my Sony Blu-ray via me TV and Beam Gen 2 in Atmos but this isn't very convenient  as I want to stream directly to my ERA 300 which is in a different room Hope this clarifies

Roger

Hey ​@Roger.S, thank you for the quick response and clarification!

Allow me to add that Spatial Audio on Music Library is not currently supported.

I’ve marked this thread as a feature request and forwarded it to the appropriate teams for consideration.

Hi,

Thanks very much for the reply. It does actually work. I have downloaded some tracks from https://immersiveaudioalbum.com/  with Dolby Atmos, these are Dolby Digital Plus in an mp4 container.

When played through the Sonos App they show up as Dolby Atmos and work fine into my Era300

But to have TrueHD requires support for mkv or mka

Roger

Hello ​@Roger.S,

When something is not supported by us Sonos, it doesn’t mean it wouldn’t work. It’s simply the fact that we cannot guarantee it would work.

I’m glad it works for you though! 

Thanks for the reply, I understand