One other thing to consider is the volume out level on your computer. If that's set too high, it will distort badly. Try setting your receiver to a volume maybe a bit louder than you would normally play other music sources, and then adjust the level on your computer to sound good with that. Lowering the bass level in your sound card may help too. There are a lot of different things going that route that can cause problems, so it may take some playing to find out how to minimize them as best as possible all at once.