My PB 12" 1.33Ghz has been a great machine, but for the past week or so the fan has been running constantly. Whether I'm using tons of programs or it's just sitting still on my desk with the lid open. Doesn't matter, the fan is always purring away. It didn't used to be like that. The fan used to only kick on when I was doing heavy-duty tasking or resting the PB on the bed. Has anyone else noticed a change in fan behavior? I was wondering if it were software related. My power settings are on automatic and I'm on OS 10.3.7 I did I virus check and repaired permissions with disk utility but no such luck. Don't really want to take it in.... Thanks!