No, BSPlayer does not cause this.
Unfortunately you do not provide any further detail about the movie-file and/or the codecs you use. Also if it happens with only one type (codec) of movie-file or just with any. (See item 2 of my
Help-to-Help post for what I mean)
It may e.g. be caused by settings of ffdshow, XviD-codec or DirectVobSub.
In the (configuration)options of these programs there is also a possibility to "flip video" or "flip screen" or similar. Try if changing its present setting solves the problem.
P.S.:
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