I have a 2008 Q7 Premium 3.6 S-line and love it! But, when I start the car cold, there is a slight knocking sound in the dash. Also, when the climate control is on auto and the car comes up to temp, there is an annyoing squeaking (sounds like a fan) on the passenger side. Any advice? Anyone out there ever change a rear 12V plug? My cap broke and my slack dealer sent me the insert and said it was a "breeze" to install...nice.