I have a MacBook Pro 3,1 running 10.5.3 After upgrading to 10.5.3 from the standard version of leopard on the dvd, my sound went from stereo to mono on all output devices. Doesn't matter if it's headphones or the built in speakers, it's always mono. I can't find anywhere to set it back to stereo and it's really really annoying. Anyone had this problem before? If so... any solutions?