Okay, this is a very weird problem, and I'm not sure how to fix it. Basically, I'm running Tomb Raider from this installer, and it's working great in DosBox, except for one thing:

The stereo balance is off. This is the only way I can describe what's going on. When I'm in the Title Screen, all sound effects come out of the left channel. When I'm in game, sound effects will come out of the left channel, but when I, say, fire my pistols while rotating, the sound will go from the left channel, to stereo, and back to the left channel.

Just what exactly is going on here, and how can I fix it?