I installed the 10.4.9 update on my macbook and now its got a constant fan sound!!! it had no sound before and now its on constantly. its the quiet sound (the one that used to make the mooing noise but now its like a constant quiet moo). anyone else experiencing this? what do i do? can i remove the update without much difficulty? p.s. there's no additional processes running - processor usage still minimal and the temperature is still normal...macbook only feels slightly warm at the bottom as usual. and usually when its like this it'd be completely silent.