Garageband is the app I've been waiting years for. Wonderful. But, I went out and bought an Edirol UA-20 audio capture USB box because the line-in level is so low just plugging a guitar straight into the back of my G4 Dual 867. OS 10.3. I've fiddled with the settings, but even the very lowest latency I can achieve sounds terrible, and makes playing anything impossible. I can't believe musicians can actually use this. All the literature, and recommendations on the internet say that this product has excellent reviews for latency. What am I doing wrong? Can anyone recommend specific settings?