Great news. Turns out the problem was the GX setting in the Asus Xonar D2X settings.
Turning that off solved everything, theres also no more crashing on exit. I suppose Asus never ironed out the bugs with that function. It doesn't seem to affect sound quality much anyhow, so I'll just leave it off.
I used to play this game tons years back, I had a level 38ish character, I'd beaten pretty much everything in the game up to Knights of the Nine. Now I get to see what the fuss is about Shivering Isles..
Thanks everyone for the help !