My warranty just went out and my pop up Nav screen shakes and rattles for 5 seconds when the car starts up everytime for some unknown reason. The audi dealer says they have to replace the MMI Carrier Assembly and it will cost me $350 for the parts and $400 for the labor. Does anyone know where I can get this genuine Audi part for less anywhere??? They told me the part number is 4E0857275E
-2006 Audi A8

any help is greatly appreciated