2013 all models seems several shades darker?

I'm guessing (hoping) this is a silly setting I can change but I spent some time looking and can't see anything obvious.

Since I loaded 2013 on a few months ago all my models seems darker. I did a clean install I hadn't changed the scenes in 2012 so can't understand why models appear darker in 2013. Dosn't seem to matter what scene I change to the problem persists.

To counter act the problem I'm raising the luminous intensity on the colours.

I can post some pics of the dark models if an easy answer isn't available to show the problem.

SolidworksGeneral