Behringer UCA202 & Macbook

[mickd]

I can use it independently as a sound card, which is fine, but what if I wanted to use it for just headphone monitoring and my internal core audio for playback. Is this impossible?

[WonderBred]

Nope. You need to use one sound card that has at least two independent stereo outputs. Can't use more than one audio device/sound card in Traktor (or any other similar software AFAIK) at a time.

Using more than one sound card would be almost impossible to get working reliably anyway, since all cards have different latencies, bus types, etc...