man getting the jb3 to work with some copies of XP is an absolute nightmare.
of 4 or 5 different computers i've (tried) to hook it up to, all running xp:
one took me an hour of reinstalling and uninstalling play center and the jb3 drivers to finally get it to work
one worked fine with the jb3 then a few months later would not recognize it and to date will still not recognize it
one refuses to work with any version of the drivers, creative playcenter or the sveta portable amp
dunno what the trick is, thank god my primary computer has no problems recognizing it (knock on wood)
good luck