I am getting occasional changes to the monitor colour, as if the calibration has been lost (subtle change of colours). I can correct this by running monitor preferences and clicking on the colour tab.
Is it possible this is being caused by Time Out (since it alters the monitor to a grayed-out state)? Could it be that Time Out doesn't restore the monitor correctly every time after a time out?
Apologies for not being more certain about this, but it is tricky to establish exactly when the problem happens.
I have a MacBook Pro running Snow Leopard, with an external monitor.
Re: Possible monitor colour corruption
No, Time Out wouldn't cause that. When a break concludes, the color is removed completely — it is implemented via a semi-transparent overlay window, which is removed after the break.
If any doubt, you can quit Time Out when not in a break and confirm that the colors don't change.
Good luck in tracking down the cause! I know it can be tricky to eliminate possibilities, but I can confidently say that Time Out would not be one of them.