Hi, I have an A3 8P1 2006 model. It has single din radio so I did the research and upgraded to a double DIN unit. I took the cage and climate control unit as well as the buttons I needed from a 2004 model. I'm not sure if I'm perhaps being paranoid but when it's in AUTO mode the fans seem to stay on low regardless of interior or exterior temperatures and regardless of engine temperature. I set the temperature as high or as low as I want and the fan speeds never seem to change. I can't even feel air coming from the blowers. If I take it out of auto mode I can set fan speeds to anything I want as expected I can hear and feel them blowing at the set speeds. What I have noticed is that I can drop the temperature to the lowest setting if 16°c whilst on AUTO even on a hot day and the fans won't spin up, but if I change the temp down to LO, the fans will come on full speed. The unit looks exactly the same with the same buttons and the same plug fittings as my old one did, the only difference is the size of the fascia of it as it's designed to fit the double DIN cage and my old one that came with the car was designed for the single DIN cage that came with the car. Is this normal or is something wrong? I'm wondering if the unit is perhaps incompatible or if it's broken? From the research I've done I should be able to fit any unit until the 2007 facelift units as they are definitely incompatible. I wonder if the guts of the unit from my original one will just drop into the plastic housing of this replacement 2004 one? Does anyone have any ideas? Thanks in advance.