It sounds like the HD accessing data and parking. Do a GoogleMac search, and you'll see that happens quite a bit. My iBook (clamshell) did it quite a bit in OS 9, but not nearly so much in OS X. In 9, I used a little program called APMTuner or something like that to change the sleep time default. Gary Ron Reames wrote: > My 600mhz iBook has started making random clicking noises. It sounds > like morse code. When I rebooted last night it stopped. > This afternoon it started again. There is no cd in the drive. Any thoughts? > > Ron > >