BTW... Upgrading to iTunes 10.6 is definitely the problem. When I go to my laptop and ask iTunes to play through all four external speakers that I have installed throughout the house, everything works just fine, just as it always has year after year.
I therefore tried to re-install the previous version of iTunes from Time Machine, and from Apple site download. In each case I'm informed I can't install the previous version because a more current version is already installed. If I try to trash iTunes, I'm told I can't because it is part of the Mac OS X Operating system.
Anybody aware of a work around to get me back to my previous version of iTunes? iTunes 10.6 (40) is causing
my system problems.