I recently received an SM57 and an M-Audio Fast Track which connects to my laptop via USB (and is thus powered through this connection). The Fast Track has a headphone jack on it with which I can hear either the laptop audio output or what I'm recording live, depending on the mixer knob setting. I use Audacity to record my tracks, usually, which has an option to record new tracks while the previous tracks are playing. This makes recording songs solo very easy. However, when using my new Fast Track, when I try to do this (record and listen at the same time), the audio output from the laptop becomes heavily distorted. Is this problem due to the fact that not enough power comes through the USB to power both my mic and my headphones? My headphones are slightly high impedance, if that could have anything to do with it. Any recommendations? If there is a similar product to the M-Audio Fast Track that is externally powered, and if that would indeed fix my problem, please suggest hardware. I can still return this thing if necessary. Edit - Actually, I just tried it again, and it's working well. Nevermind.