If you are referring to the 987/997 mirrors then the whistle is coming from the small 1mm gap in the middle. This is a known problem in the 997 cars and I assume it was carried over to the 987. It is because right in the center where the seam is (window side of the large air opening), the seam is lose (about 1mm) and there is no way to tighten it.
The only solution so far that has been a good one, is to use a small piece of clear bar to block the gap.
Hybrid Mode
