A5 Cabriolet rear view screen won't engage

[VicW]

I have 2012 A5 2.0 TFSI S Line Quattro Cabriolet  and over the last week or so the rear view screen has failed to connect fully. When I engage Reverse it initially connects and displays the rear view screen then quickly disconnects and reverts to whatever screen was showing initially. Also occasionally one or other of the power folding wing mirrors fails to locate in the correct position on starting the car. Am I going to have to remortgage my house or is it a known issue and reasonably easily fixed please?