Raven, I'm glad you did.
Unfortunately, I have a similar problem. I'm running the same X-Files game that I got from Ebay, and when I loaded the game, the sound was fine until I went back to the main menu, or loaded a game, and then the sound disappeared. Video was fine, however. I found out that I should uninstall Quicktime, and re-install the version that came with the game. It worked ONCE. Now, when I load it, I get sounds, but no video. I'm banging my head against the wall. Does XP have a DOS Box? I've done everything else mentioned except that.