Hello chaps,
After over a year fighting with Volvo dealers. I won and they had to replaced all driver wing mirror with wiring for new
happy days so far no more issue with mirror position after reversing or after access to car or outside temperature sensor.
There was the faulty wire inside the mirror that caused problem and also was interfering outside temperature sensor.
Looks like this problem should be reported as recall. I have got loan car during my car stays with them and v90 reg 21 had exactly same problem
.