In case anyone still has problems with Nestopia and their X-Fi card:
I solved the chopped-up sound by using ALchemy (Creative's DSound->OpenAL wrapper).
I set buffers to 4, duration to 1, and with a Nestopia sound latency setting of 1, I don't get any crackling or chopped-up sound anymore.

Seems like the wrapped dsound works better than native dsound, which is kinda hilarious.

Last edited by regha; 11/18/10 09:58 AM.