Can someone help me out here. I was using Windows XP, but then I upgraded to to Windows XP Pro. After the upgrade I no longer have sound. When I try to play music using Musicmatch Jukebox it gives me a message saying it can't access the sound card device because some other application is playing audio. I don't have any other applications installed on my computer that can play music. I did have Real Player, but I removed it. Any help is greatly appreciated.