can logic to recognize a usb mic and still use core audio?

i am using logic pro8 on a macbook g4 to record an audio diary of my travels in new zealand.

for this i thought an external mic would be a nice addition to using the internal condenser, so i purchased a CAD usb condenser mic that is basically plug and play. awesome, computer recognizes, sweet. however, in logic to get the mic to register for recording i so far have had to go preferences/audio/devices and toggle from the core audio to the mic which shows up as "generic usb device" which is fine, but by disabling the core audio i lose playback of previous tracks into my headphones. i have looked at the (input) button on the mixer screen to see if i can just activate the mic there, but no dice.

what can i do to get logic to recognize the mic and still use core audio for playback?

lucasmeyer666@yahoo.com

thanks