@Zillion_ said:
Fixes the movie / episodes stopping after 30 minutes, but causes the subtitles to stop after 30 minutes again !
That would be a different issue. Please raise as separate forum topic with logs and details of what happened / what time and what media file. Als please provide media info xml
See
https://support.plex.tv/hc/en-us/articles/201643703-Reporting-issues-with-Plex-Media-Server
https://support.plex.tv/hc/en-us/articles/200250417-Plex-Media-Server-Log-Files
https://support.plex.tv/hc/en-us/articles/201998867-Investigate-Media-Information-and-Formats