A year or so ago, I think a bicyclist had a pretty rough encounter with my parked S420's driver side mirror. I noticed the tinting in the mirror slowly started disappearing to the bottom, and the housing that contains the mirror and motor never locks tight to the door. When I go over cobblestone or even a bump in the road the mirror shakes and sometimes sags, whereas the passanger-side mirror is perfect and tight. Folding and unfolding the mirrors with the switch in the cabin does just that but does not re-tighten the housing, and popping it back with my hand when it sags only works until I run over another bump or even just close the door. My question is: does anyone know if this is an easy fix to get the housing to fit snug against the door, such as replacing a pin or bracket or is this something that requires an entire replacement?