Strange heating problem

[samp49]

Hi
I have X3 2.0d Xdrive 2009, automatic A/C. Now in winter when having outside some minus 10-15 centigrades cold I have the following problem:
. the car has been parked for couple hours after a long drive with the motor fully warmed
. when starting to ride again very shortly all the windows get frozen and seems that the A/C control buttons have no proper effect
. when driving 8 to 10 kms more (trying to keep a hole in the windshield for seeing the traffic) the A/C, heater starts to work properly again and the windows get defrozen

I took the car today to the dealer. They checked the software, which they told was ok, and noticed that the fresh air filter was wet - it was changed. But I suspect the above problem persists.

Has anybody of you experienced the same or any idea why this happens and how to fix it?

Merry Christmas and Happy New Year!