I am trying to use CompUSA 80 min. CD-Rs with the CD-RW/DVD drive in my sister's iBook. I've tried using Toast and the OS 9 & X built-in burning program, but the writer writes for a while then gives an error. I have used some regular 74 min. CD-Rs without any problems. I bought a 50-pack of these CDs, I have 31 left. I was able to burn a few before, but I can't anymore.