I have a Soundblaster Audigy ZS in an XP SP2 system. Suddenly today I stopped getting sound. When I go to Device Manager and look at Sound Video Game controllers the SoundBlaster is there and everything looks good. However when I go to Control Panel to Sounds and Audio Devices/Audio there's no hardware listed and everything is greyed out so I can't add anything. I can still hear system sounds however. When I reboot everything works, everything shows up properly in Sounds and Audio Devices. I leave the computer for a while and then when I come back - no sound again. Reboot. Everything ok.