Excuse me for not reading this whole thread. I'very had a few at a bar and perused... I doubt your mirror is leaking. My New Edge had some leaking in heavy rain too. Next time it is half decent outside rub some white lithium grease across the seal above the winshield. That is a common place for vert seals to compress and/or dry out. The grease seeps in and prongs the life of the seal. I've had 2 VW verts and a Mustang GT vert and that was one of the first thints I did to the car ...and by me, I mean. My wife had two VW convertibles haha