Hi. I'm having trouble recording more than 3 or 4 guitar tracks in GB. When I try and do more I get a message saying my track couldn't be played back and to check the optimization pages in the help documents. I've followed those suggestions (close all other programmes, lock tracks etc) but I still only manage to get only one more short recording. Im using a MacBook Pro (576 GB free on HD, 2.4 GHz, 4GB RAM, 5400 RPM HD, 1333MHz) I've seen people with less powerful machines with 40+ tracks, any ideas what I'm doing wrong? Thanks in advance for any suggestions.