Server Version#: 1.41.0.8992
Player Version#: 10.20.0.1427
I connected my Chromecast TV directly to my Yamaha AVR with Earc. It is capable of all the major codecs and Chromecast itself detects the formats. It is currently set to auto.
When using Netflix / HBO / Prime I can see that my receiver detects the correct output (be it TrueHD / DD+ etc).
With Plex however the only output I see on the receiver is PCM. I tried different source files (TrueHD, DTS etc.). All resulting in PCM output.
The Plex server console shows it is not transcoding the audio. So why does the receiver say it’s PCM?
Are you using a Chromecast with Google TV, with the Plex Android TV app installed?
In the Plex app settings: Passthrough = HDMI.
Test using media with Dolby Digital or Dolby Digital Plus audio.
AFAIK, the Chromecast does not support passthrough of TrueHD audio, so it will be converted to another format. I do not know if it will passthrough DTS formats.
The Plex Dashboard shows what happens on the server.
If the client device is modifying the audio, the server will be unaware and it will not be reflected in the Dashboard.
Example: Older FireSticks do not support DTS passthrough. The FireStick (not Plex) converts DTS to multi-channel PCM. The Plex Dashboard shows Direct Play and an AVR displays multi-channel PCM.
Thanks, I forgot to mention that passthrough is set to HDMI.
EAC3 5.1 → DD+ (No transcode)
AAC 5.1 → PCM/Dsur (No transcode)
DTS-HD MA → PCM (No transcode)
TrueHD 7.1 → PCM (No transcode)
Example: Older FireSticks do not support DTS passthrough. The FireStick (not Plex) converts DTS to multi-channel PCM. The Plex Dashboard shows Direct Play and an AVR displays multi-channel PCM.
That would explain some of it. However TrueHD does get outputted by Netflix so it should be capable. And doesn’t the transcode involve a lot of CPU power for the Chromecast?
Passthrough not supported by the device, so it converts the audio to PCM. PCM is lossless, so there should be no quality loss.
If the audio is TrueHD + Atmos, then Atmos info is lost in the process (and converting to DDP + Atmos is not possible).
If you want TrueHD + Atmos:
a) Try sideloading Kodi + Plex plug-in. Kodi has its own audio engine and may pass TrueHD + Atmos.
b) Use a device that supports TrueHD passthrough. Basically, an Nvidia Shield or a FireStick 4K / 4K Max Gen 2. The Shield will passthrough all DTS formats. With the FireStick, only the core DTS 5.1 is passed.
Either the Chromecast or the Yamaha AVR (or both) may not support sending AAC over an HDMI connection.
Example: I’ve an Nvidia Shield connected to a Denon AVR. The Denon does not support receiving AAC on HDMI input, so the Shield converts it to PCM.
I tried installing Jellyfin server and client and tried the same movies. TrueHD still fails but DTS does work with Jellyfin. It musn’t be easy all these different formats for developers.
