So your problem still remains unsolved since you first posted it almost 10 months ago now. I then thought and now think again it could be caused by (unintentionally) changed settings. So maybe let's rule out that possibility first, using a rough remedy method.
You're under XP so the default location of the file we're looking for is located under:
C:\Documents and Settings\[your_name]\Application Data\BSplayer\
or alternatively if you opted to save it in BS.Player's installation folder it should, by default, be in:
C:\Program Files\Webteh\BSplayer[Pro]\
Anyhow, it concerns the file
BSplayer.xml
With BS.Player not active, please rename this file (e.g. to xSettings.xml).
By doing so BS.Player will have lost all its settings (which you may have changed) and BS.Player will upon its next startup simply create a new settings-file BSplayer.xml with all settings at "default".
If your problem continues in BS.Player after that, we have at least ruled out that possibility.
And you can (again with BS.Player inactive) restore your old settings (if you want to), by deleting the new BSplayer.xml settings file and renaming the old file back to BSplayer.xml.
Let's know what happened.
(You're still using the same keyboard as in February of this year?)