4.1 speakers and musicmatch jukebox

Hi all,
i have a creative inspire 4.1 speaker setup. It works very well except when i use musicmatch jukebox to play music. It works well with WMP.
When i use musicmatch jukebox only 2 of the 4 speakers produce sound.
The rear speakers don't produce sound at all.

Can anyone help me fix this??

thanks.