XL-h1 viewfinder problem.

My XLh1 was on a shoot yesterday (someone else using it)....and the viewfinder "all of a sudden" got really dark. The recorded image was fine, it was just a viewfinder issue. I know the cameraman who was using it likes to explore gear and push lots of buttons, so I searched through all the menus...nothing looks out of place. So, has anyone ever seen this happen before? Did something in the viewfinder blow out?

I quickly searched the interwebs for a replacement, but it looks like the only one you can get is the B&W version...any advice would be appreciated.

thnx