Well, e.g. like version of BSPlayer, type of subtitles and type of movies that gives the trouble (perhaps quote the info mentioned under rightclick > Options > filters > advanced).
(Did you read something of my Help2Help-post?)
I don't suspect anything yet (without info).
http://bsplayer.com/forum/viewtopic.php?p=27527#27527 http://bsplayer.com/forum/viewtopic.php?p=27661#27661