For example, if your Plex is language is set to English, but you mark a French subtitle track to be forced on, Plex will NOT force that track on. If you flag a subtitle track that is in a different language than your selected preferred language in Plex, Plex will NOT force that subtitle on. If you’re remuxing or adding in downloaded subtitle files to your MKV, I think you need to make sure they have a language flagged in the MKV file. So they may cause some slowdown (I cannot confirm this though). I don’t have this issue, but the subtitles included with blurays can be more intensive for a video player than downloaded SRT files. You’ll have to know which movies have a subtitle track for foreign language parts. If you don’t burn all subtitles, or at least all subtitles in your language, you’ll have to re-burn the movie.Įvery movie has to be checked manually. You have to have burned the movie with the correct subtitle files. You will also have to source all your own subtitle files, or have Plex search them out. There are a good amount of users who have no issues with this, but also plenty of users (myself included) who had hit or miss luck with using external subtitle files.

You will also have to inform anyone using your Plex server that they have to do the same. You will have to change your Plex subtitle settings to get these to work. Any other users on your server also won’t have to change any settings. This is the only way that Plex will always turn on forced subtitles for foreign language parts without needing to mess with any settings in Plex.

In Plex you may need to rescan your library and/or refresh metadata for the movie/show. If you're all good, then go back to 'Header Editor' and click 'Save'. Then in top menu bar, click 'Header Editor', then 'Validate Values'. (optional?) I also click on the 'Default track' flag and change 'Current value:' to 'Yes' On the right side next to 'Status:' check 'Add element' (you can open your MKV in VLC or Plex and go through the English subtitle tracks to figure out which one is the foreign languages track)

On the left side click on the 'header editor' iconĭouble click on the subtitle you want to want to force on.

Makemkv how to set forced flag