Is there any fellow a4 cab owners who can help me I am having trouble with the roof on my car simply put it won't operate. can someone tell me if on your cab when you press the switch do the roof the windows go half way down can you hear the motor in the boot working immediately or is there a delay as I can't hear mine trying to work .when I press the switch the windows go down then you can just hear the catches on the front but the roof does not lift up at all any ideas or help much appreciated