MBP13 2010 - Audio output issue

Hi everyone,

I've got an up to date Lion rocking my MBP, but lately I have been having problems when I connect my external audio system. The output is mono only for some reason.. it clearly is a bug because if I restart the system I get stereo again..

I tried fiddling in the system preferences pane with no luck so far. Any idea how this behavior can be changed? (restarting the MBP everytime I come home is a hassle.. plus it used to work flawlessly)

Thanks in advance!

Edit: I am not using an optical connection to my system (should that matter).. copper only.

 

Well I have tested if this was an application dependent issue, but I have the problem with any app that outputs sound (iTunes, safari/chrome (e.g. youtube), vlc, ..)

Maybe you're talking about which application I usually run? Then there's a lot of them.. parallels, skype, adium, some X11 apps, xcode, some specific development tools (CS student here ),.. I usually end up with everything opened since i don't restart the MPB unless updates have been released.

Do you have anything specific in mind?

Thanks!