Dear Plex team,
please get in touch with this bug. It is described in these threads:
"Never had this problem before (using Plex for maybe 6month+).
Happens to all formats available to me (ac3 dts / mp4 mkv).
The TV App shows all languages, I can select them but it doesn't change the audio track. Changing via PC "Now playing" doesn't work either.
It defaults to audio track 1
When I disable DTS(DCA) under settings in the TV App and Plex starts transcoding the correct audio plays.
Windows Plex 3.9.1
Samsung Plex (3.1.0(3.8.0))
Reinstalled Plex on both systems and tried to change settings without success."
Got the same issue with KS8090 (latest App) and Plex Server 1.7.0 (latest) for Synology.
Thank you very much in advance.