OK, been thinking about it, and I'm wondering how powering mics in the field will affect the battery. I'm gonna run a laptop with a 5 hour external battery pack, powering the Fast Track (and consequently the mics) via USB. If I were to grab a battery pack for the fast track, it would't cause a problem, would it? I mean, the fast track would 'know' to take power from the battery pack as opposed to the USB connection? Just don't want to blow anything up.