Just installed the update and everything seems to work fine except that i get this "thump" noise similar to the noise when you switch of/sleep the computer. It's only audible when i have my external speakers plugged in. Every time the computer needs to make a sound you can hear this noise through the speakers and then after about 30 sec. of inactivity you can hear it again. Seems like the update switched on some power saving feature of the sound card... It sounds exactly like the sound you get through the speakers when you switch on the computer and then when you switch it off. I'm on a 15" C2D MBP. Anybody getting the same issue?