This is more expensive than Daveboy's method. But you mentioned that you wanted to enhance music quality. The Xitel cable has it's own DAC mid way which enables it to take digital data direct from your hard drive (i.e. bypasses your PC's (often crappy) sound card) and forwards it to your hifi as a high quality analogue signal.
I've used one for ages in conjunction with a Denon sound system and it's really good.
It does need configuing carefully but the advice which accompanies the product is pdg.
All of your other PC sounds then emanate from your sound system and it doesn't prevent you from using a Skype headset.