I just purchased a new 12.1" 133Ghz PowerBook with the SuperDrive. It's only a couple of weeks old, and I'm questioning my sanity. I've noticed a quiet, yet audible click that sounds like the read/write head making a brief jump and it seems to happen with some regularity (a few times a minute). I don't remember hearing it when I first got the machine, but I could just be getting used to hearing the disk work. S.M.A.R.T. says that all's well and all the Dick Utility diagnostics are good too. Is this normal behavior or am I just being too sensitive to what is generally a very quiet machine?