Sound plays but won't play music.

Similar to radiohazard's problem my speakers can play sound but cannot play music (Shoutcast radio/pandora/YouTube videos ect.) My speakers are connected to a sound card called SB X-Fi Go! Pro and it got the job done up until this point. I tested what is going on, in fact it was playing country music on windows media player a minute ago now it doesn't want to play any internet radios. My desktop is a Compaq with windows xp.

Also I am new to this site and hope to have my tech problems resolved here.