I've been having the exact problem! My car has been in the shop for over a week now as my rear camera has done a few wierd things lately. I've had issues with the rear camera before and they've replaced, changed the CCC unit and it was ok for a few months until recently it started to blank out, put itself into test mode which shows a bunch of colors, and finally, it goes into Dual Nav mode showing two maps.

The dealer opened a PUMA case and I e-mail them pictures of what happens. So far, they said the techs in both Germany and SC are stumped.

I'll keep you guys posted as to what the fix is....

Chris