Sins crashes on quit, kills my sound

I just got SoaSE and love it, but it has an annoying little problem.  Everything runs great until I quit the game.  The game appears to quit successfully (i.e. no minidump), but the traditional window pops up saying "Sins of a Solar Empire has encountered a problem and needs to close."  Thereafter, I cannot play any sounds on my computer.  If I try to set the volume, Windows says "the volume controls could not be opened because there are no mixers available" (or something to that effect).  Windows Media Player encounters errors when trying to play music files.  None of the Windows sound effects work.  Basically, my computer is mute until I reboot it.

I use Windows XP.  My version of SoaSE has neither of the expansions but has the most recent patch.  I don't think I have a sound card per se, just an integrated audio controller called "SigmaTel C-Major Audio."  As far as I can tell, there aren't any relevant driver updates for it that I need.  Anyone know what's going on?