mirrored image

[wildwood]

I have a ioon 7 inch TFT LCD in-dash Monitor which started playing up some months ago. The picture started flipping over so that it had a mirror image picture. It is most noticable ofcourse when there is writing on the screen such as with the credits of a DVD. First it went over occasionally, but for the last 2 months it is the wrong way permanently.

I suspect something has triggered the flip-over mode which is present in many car-monitors for reversing cameras. Anyone have any ideas on how to fix it please?