Hello, I have a iMac G5 1.8GHz w/ 512MB of RAM I use for Garageband recording. I also use a M-Audio FastTrack guitar/mic recording interface for recording guitar/vocals. Sometime when I am recording, the sound just completely cuts out, I can't playback or hear the recording at all, but I can keep recording, without monitors and sound. Is there anything I can do about this? Thanks.