Open your sound mixer, and see if the volume for Fallout is the same that the others.
In-game, go to "Preferences" and put everything at max (not just "Master Audio Volume"), and save the game.
Or edit fallout.cfg. Go to:
If that doesn't make any difference, then I don't know.
I already found the problem in that I couldn't find preferences for some reason. But the config thing I didn't know about, so I'm gonna mark this as a solution even though I already solved it cause you just taught me something I didn't know. Hell, I didn't even know Fallout had a config file. lol So, THANK YOU.
But, yeah, I found preferences after I posted this and then turned the volume up, pretty simple lol. But for some reason I couldn't remember how to find that yesterday and I was convinced there was no in-game volume control. lol. Long time since I played this game. Long time.