Audio issues in WinXP

I've got an issue here.

The volume controls (ALL of them) in WinXP are greyed out. Master Volume is not showing up on the list of volume controls. Windows Audio (the process) is running. Any ideas, folks?

Check the device manager.  (Right-click "My Computer" either on the desktop, the Start menu, or Exploder; choose "Manage" from the pop-up; choose Device Manager)  Does Windows think your sound card has problems.  Or perhaps Windows doesn't think you have a sound card anymore?