Ron: You're going about it the right way. Step by step. The Applecare people will take you through the same sort of thing. Gary Ron Reames wrote: > OK, I think I'm on to something. > First of all, this problem started when I upgraded to 10.2.5. > Now, the clicking is related to running on battery power. When I plug in > the power cord, the clicking starts. I've got to replicate this a few > more times before I report it to AppleCare. > > > Ron