I've got a 2013 A4 Allroad, owned it for a while now. I recently noticed a loud metallic noise from the rear of the car. When I had a look, I could see that the bolts on the driveshaft/diff flange were making contact with the underside of the car. I recorded some video with the car jacked up and could see significant deflection of the differential. It rotates enough on acceleration and hard braking for the front of the diff to hit the underside of the car. The crossmember mount and bushing is completely deteriorated but I don't think that's a hard connection to the subframe. Meaning that it would not prevent the diff from rotating upwards. I'm trying to figure out what to address in order to resolve this issue.