What you are doing is exactly what you should be doing. The only suggestion I would have is to try to slow down the burn speed, or try a different CD manufacturer to get better results. Go to "Preferences - Advanced - Burning" to change the type/speed of the burn. In theory, it should work at any speed, just throwing out the options to try. You might have a bad writer in your computer, but I would try a few other options before you contact apple.