We're having the same discussion at Euro LOC at the moment. My CD-Player starts to make problems too. Although I changed nothing in the last couple of months - same CD's (CD-R), same burner, same speed, same program (iTunes/MacOS X 10.3) - my in car stereo comes up with "error 1" quite often when playing newer CD's. As someone other here mentions iTunes - perhaps Apple has changed something in newer versions that causes problems with CD's in our cars?
I will try to burn the same CD on my PC with the same media, speed etc... but with another program than iTunes. If it works that may indicate a problem with iTunes