My typical workflow for adding new video content to my library is:
- Purchase and download item from iTunes
- Convert downloaded file from m4v to mp4
- Move converted file to PMS directory
In the conversion process, I copy all the video, audio, and subtitle streams as they are. When I play the item in the Plex app for Xbox One and select the TX3G subtitle track, no subtitles ever appear.
I'm not sure if I'm something doing wrong or if maybe Plex for Xbox doesn't support TX3G subtitles? I'm not even sure how to troubleshoot.