I happen to glance at my PC's toolbar and noticed it said my speakers were muted. I opened the volume controls and it won't let me uncheck the MUTE box...I haven't done anything different since I was last listening to them a few days ago. I've gone into control panel, and my PC's sound card controls and can't uncheck any of the MUTE buttons. I'm running XP Home w/ SP2. Any thoughts on how to fix?