Can't set color profile
The system no longer accepts setting a specific color profile. When I select a color profile OS X instantly adjusts the screen and displays it correctly, but after half a second or so it falls back to the default profile.
It has never been like this before.
Setup: MacBookPro5,3 OS X 10.6.8 and Cinema Display 23" (the old one with matte screen and DVI connector).
Note: I have resetted NVRAM and PRAM and ColorSync Utility -> Profile First Aid -> Repair. But that didn't change anything.