Ok I know this is incredibly ghetto, but a very small bead of clear silicone on the front side of the mirrors where they meet up to the base will fix the whistling so many people complain about.

Completely, and utterly quiet now. I know it's ghetto, but it was an incredibly annoying whistle, and I like driving with my windows down.

Mark 1 item off the list of things that are going to get remedied in the next coming days. Next on the list: rattling exhaust, leaking/whistling sound from the driver's air vent only when A/C clutch is engaged.

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Interesting, any chance you could take a picture of the exact area where you applied the silicone?

 

done. I hope this helps. Now it's completely silent!!!!!! NO WHISTLING!