Hi @DrearierJester.
Thank you for reaching out to Sonos Community.
Can you please submit a diagnostic report for us to see how your Sonos speakers are setup?
In that way, we can provide some recommendations or correct some settings if needed.
If you need help with any other information, please be sure to let us know.
So I have the ATV 4K (using the Infuse Pro app), LG C9 connected via ARC port (enabled eARC) with the Sonos Arc + HT (Sub Gen2 + OneSL) I have a source file playing with Dolby TrueHD 7.1 track but I am only receiving DD 5.1 on the Sonos system as verified by On the App.
Is this normal ? Shouldn’t I be or supposedly be getting Atmos sound on the Arc Home Theatre?
Netflix, Disney+, and Dolby Atmos test files (playing from Infuse Pro App) are working fine with Atmos though.
Welcome to the pain all Plex / Infuse / Apple TV 4K users are experiencing re: TrueHD / Atmos.
Every piece of your chain is TrueHD / Atmos compatible…. except one - the Apple TV itself.
Unfortunately, the Apple TV 4K does not support TrueHD in any way. Neither Plex nor Infuse will pass it through as tvOS doesn’t support TrueHD. The Apple TV (or the app, never quite been sure which) will decode the TrueHD, repackage it as multichannel LPCM and send it out in a Dolby MAT container which the TV may or may not do some additional re-encoding to and the Sonos Arc will see as either Dolby Digital 5.1 or Dolby Digital Plus 5.1.
The reason you’re getting Atmos from everything else, including the Atmos test files played via Infuse, is that they’re all encoded using Dolby Digital Plus (or E-AC3), a lossy codec that can still carry the Atmos metadata (which is what all the streaming services use to preserve bandwidth).
The only solution I’ve seen to be able to get Atmos / TrueHD from BD rips via Plex / Infuse is the Nvidia Shield as it does support TrueHD throughput. Apple TV, very unfortunately, just won’t do it.
There’s even a petition for it ;-)
https://www.change.org/p/dolby-mat-v2-0-or-full-bitstream-audio-passthrough-support-on-the-apple-tv-4k
Sorry to be the bearer of bad news. I’ve got a rather sizable BD collection ripped to my Plex server that I’d love to be able to play in Atmos or True HD on my Arc, too.
Hi @DrearierJester.
Thank you for reaching out to Sonos Community.
Can you please submit a diagnostic report for us to see how your Sonos speakers are setup?
In that way, we can provide some recommendations or correct some settings if needed.
If you need help with any other information, please be sure to let us know.
Diagnostic reports? For something that literally won’t work? Come on, guys….