Reply to iTunes playback through S2 sounds awful

I've been having an issue with iTunes playback through my S2 soundcard.

Seems like anytime I play a song, there's some serious stuttering. Not like a CD skipping but a choppy slowing down kind of sound.

I can't figure out what the problem is, I turn off my wifi, I set my computer to run on best performance, and it seems to do this on every track.

Playback on iTunes without the S2 is fine however. When I play iTunes through my computer speakers I have no problem whatsoever.