Please share the log. (Tools -> Messages with verbosity 2)
If using multiple external subtitles files at the same time (e.g. some_movie.avi, some_movie_english.srt, some_movie_greek.srt), convert subtitles file encoding to UTF-8.
See
viewtopic.php?f=14&t=99532&p=335037
I think it's a bug^Wspecification that file encoding setting is ignored and is treated as UTF-8 when playing with multiple external subtitles files.
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