We could use a bit more information:
What build of BSPlayer are you using? The latest version is 86 build 501 of Sep 6.
If you have a pre-500 version: first install 500
http://www.bsplayer.org/dlfile.php?s...lay086.500.exe
and subsequently place the substituting files of build 501
http://www.bsplayer.org/dlfile.php?fname=bsplay.zip in BSPlayer's installation directory).
Further:
Can you by any chance tell us what type of video-file it is and/or which compression (=codec) is used for it?
You can easily find out using a program like GSpot or AviCodec.
http://www.headbands.com/gspot/ resp.
http://avicodec.duby.info/
(This will also tell you the audio type).
Please let us know.
(P.S.: Volume is not turned down to 0 by any chance is it?)