Current MacBook Pro Seizing Up Under Snow Leopard 10.6.1 (often within Safari)

After I installed 10.6 on my June 2009 vintage MacBook Pro, I started getting the spinning rainbow disc way too often. Most of the time it would be inside Safari, but not always. Worst of all, it wouldn't be limited to the current application mouse clicks outside the app wouldn't switch me to another app. I couldn't use cmd-tab to switch between applications -- no app list popped up.

After about 10 seconds the disc would disappear. I wouldn't get it for a few minutes, and then randomly get it again. It didn't appear to be connected to any behavior unless you include things like clicking on links and putting text into form elements.

I finally found the fix posted by Guttiwuts on the Apple Support Discussion boards. The culprit appears to have been the Core Audio daemon, /usr/sbin/coreaudiod and the solution is to remove:

/System/Library/LaunchDaemons/com.apple.audio.coreaudiod.plist

and restart. That stops the daemon from starting up and appears to COMPLETELY FIX the problem. I'm guessing that Core Audio is tied intimately into the kernel and is given high enough priority that its misbehaving steps on other processes access to the kernel.

I have no idea what this does to you if you need Core Audio for whatever it is you do (make music, probably). Maybe it doesn't matter with well behaved music apps. Don't know.

Interestingly, this did not happen at all on my two year old white MacBook, though I ripped out the plist just the same. I have to guess that there's something about this new hardware that makes it worse.

Strangely, there aren't a ton of reports about it. Kind of frustrating and it makes me hope that Apple's going to address this in 10.6.2.