There may have been a bug in that version of BSPlayer.
This post (7th March 2004) seems to report a similar problem as yours.
Unfortunately the versions which I still have on my PC for testing purposes do not include that version, so I'm unable to test.
(
I keep version 0.86.501 version 1.37.826 (version 1.41 Pro) and most recent version installed (as per today: 2.23.953)).
So I would suggest to upgrade to one of these versions.
As you also mention having no sound for any application, maybe first try to re-register quartz.dll:
http://bsplayer.com/forum/viewtopic.php?p=15157#15157
(which often seemed to do the trick under Windows-versions prior to Vista).