Please don't instruct the server to transcode hd-audio!

[JohnnyBr_v0]

Hi there.

I use dolby’s mp4muxer to mux my Dolby Vision bluray movies into a mp4 container. (mp4muxer stores both dv layers and writes the secret data enabling dv on playback).

Then I add lpcm 7.1 audio (converted from truehd) with mp4box to the mp4 container.

Now they play fine with XPLAY and from usb stick.
However the Plex app instructs the server to transcode the audio into ac3.

I know technically the TV will do the same as you cannot output hd/lossless-audio over arc unless you have the latest 9-series tvs with e-arc and hdmi 2.1.

HOWEVER…

When the plexserver transcodes the audio into ac3 it will lose the so called secret data stored in th mp4 container, losing the ability to activate dolby vision.
So they’ll play with HDR10 only instead.

So I’d like to request an option in the lg plex client to NOT tell the plex-server to transcode lpcm, truehd or any other audio format which can technically not be distributed over arc.

So simply direct play the movie instead!

For more information regarding these dolby vision see this thread:
https://www.makemkv.com/forum/viewtopic.php?f=12&t=18602

[anon18523487]

But if PMS doesn’t transcode the audio, then you wouldn’t have any sound.

[JohnnyBr_v0]

Yes I would… because if my tv detects hd-audio like lpcm 7.1 or truehd or whatever… it’ll transcode it internally on its own when sending it over ARC.

Like I said the movies are double layer Dolby Vision (two hevc video streams) and a lossless lpcm 7.1 audio track muxed into a mp4 container.

They play fine from usb media and the XPLAY plex client will simply direct play them as well.

[anon18523487]

Of your TV supports 7.1 lpcm, then turn off passthrough support and it should direct play.

[JohnnyBr_v0]

Thank you.

Where should I find the option to turn off passthrough support then?
There’s options in the Plex app settings for enabling/disabling ac3, dts etc.