What kind of subtitles?
If I rip a Blu-Ray disc to MKV, the captions remain in PGS format. If I play these videos through my Blu-Ray player, the captions are recognized but not displayed. If I rip the same video into the M2TS container, the same captions are now displayed. My guess is that the BD player recognizes the M2TS container as a BD disc, while the MKV container is considered something else and won't engage the correct processing mode.
Now if they're VOBSUB captions, then they should be working. Please provide the video information using either MediaInfo (Windows program) or FFMPEG (command line ffmpeg -i file_name)
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