No sound while playing Star Wars Battlefront 2

Ok, a few things to know before you can answer this:
1. I have ran this game before! Perfectly, without sound problems.
2. This is the steam version.
3. I cant adjust any of the options below the draggers. I cant edit the mixer config, so I think that's a part of the problem.

So, if anyone could please help me, It would be very appreciated.
Specs:
Windows XP SP3
Video Card: ATI Radeon X/300 X/550 X/1050 Series. (I have no idea)
Dual core
thats all i know off the top of my head.

Thank you very much!

Well, do you recollect any changes made on your computer, since the last time the game worked? updating drivers, installing win updates, changing system settings for something?

For what it's worth, you might want to backup your save games and try reinstalling the game to see if that helps.

Sound drivers are bad or missing on the steam version. Check the STEAM forums...