Question

Troubleshooting with Doby Atmos on Sonos Arc

  • 13 January 2022
  • 7 replies
  • 110 views

Hello everyone, I need the specialists fo this forum :nerd:


I have a Sonos Arc + TV LG OLEDG1, when I watch a series (with Dolby Atmos sound) on Netflix or Amazon Prime I have “Dolby Atmos” on the Arc, everything is fine but when I play an MKV file (via integrated LG player or via Plex) things go bad, 2 cases:
- if the sound is encoding in "EAC3 Dolby Digital Plus with Dolby Atmos" it’s ok I have “Dolby Atmos” on the Arc soundbar (the Sonos app show me “Dolby Atmos” on the screen).
- if the sound is encoding in "MLP FBA Dolby TrueHD with Dolby Atmos" it’s not ok I have "Dolby 5.1 multichannel PCM" which is displayed on the Sonos app (see screenshot) and not Dolby Atmos as in all other cases.


Any idea of ​​this problem?
Thank you and sorry for my english :pray:

Nicolas

 


7 replies

Userlevel 7

On the TV, make sure HDMI Input Format is set to Bitstream, Digital Sound Output is set to Pass Through or Auto, and eARC is enabled.

Hello,

It’s ok for Digital Sound : Auto

eARC support is enabled

but the HDMI input format is unchangeable (see screenshot)

 

Tests on the day :

From the WebOS multimedia player :

- if the sound is encoding in "EAC3 Dolby Digital Plus with Dolby Atmos" it’s ok I have “Dolby Atmos” on the Arc soundbar (the Sonos app show me “Dolby Atmos” on the screen).
- if the sound is encoding in "MLP FBA Dolby TrueHD with Dolby Atmos" I havne’t any sound

From the Plex player :

- if the sound is encoding in "EAC3 Dolby Digital Plus with Dolby Atmos" it’s ok I have “Dolby Atmos” on the Arc soundbar (the Sonos app show me “Dolby Atmos” on the screen).
- if the sound is encoding in "MLP FBA Dolby TrueHD with Dolby Atmos" it’s not ok I have "Dolby 5.1 multichannel PCM" which is displayed on the Sonos app (see screenshot) and not Dolby Atmos as in all other cases.

 

Is it a problem of display on the Sonos app or do I have a true problem of sound ?

Please help me !! 

Thx

Nicolas

Userlevel 7

What happens if you set Digital Sound Output to Pass Through?

In this case Sonos app displays « Dolby Digital Plus  7.1 », it’s better 😊 but it’s not Atmos 😣
Is it a problem of display or I still do not have Atmos ?

Thank you for your help

 

Userlevel 7

The Sonos app displays “Dolby Digital Plus” even when playing a “MLP FBA Dolby TrueHD with Dolby Atmos” file? What specific movie title are you testing?

Yes that’s exactly the problem the Sonos app displays “Dolby Digital Plus” when playing a “MLP FBA Dolby TrueHD with Dolby Atmos” file. 
I have tried with Ready Player One and Bohemian Rhapsody. Same problem. 
When I use Netflix or Prime video or a file encoding with « EAC3 Dolby Digital Plus with Dolby Atmos » it works and I have Dolby Atmos on the Sonos App.

Do you suspect a problem with the file ?

 

Userlevel 7

Are you trying to play the Dolby TrueHD MKV files through the USB port of the TV? If so, I don’t think lossless audio formats like Dolby TrueHD are supported through the USB connection. Stick with the lossy “EAC3 Dolby Digital Plus with Dolby Atmos” files instead.

I also don’t think the TV’s native Plex app supports Dolby TrueHD either. You need to use the Plex app on a device that supports TrueHD on the app like an Nvidia Shield.

Or be old fashioned like me and get a Blu-ray player and buy Dolby TrueHD/Dolby Atmos movies on Blu-ray or UHD disc. If you want the very best video and audio quality, you can’t go wrong with physical media.

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