I have a Powerbook G4 with a Superdrive. The drive burns DVD-R just fine but has not been able to burn a CD in some time. At first I thougt it was the media but I have not found any CD's that work in my drive. I just upgraded to OSX 10.4.8 from 10.1.2 or some older version of OSX, and just recenly upgraded to iTunes 7 as well. When I attempt to burn a CD I get an error message in iTunes that says "failed to calibrate laser power" for the media. Any idea's what the problem is? I have burned CD's on this machine in the past just fine and it burns DVD's with no problem.