Thanks for the update! I test drove 4 cars on two lots and all of them had the shake to some extent. Some worse than others. I found one that had minimal shake/vibration and bought it. I haven't tried to get it repaired thinking there would be a good chance they would replace the mirror or mounting hardware with ones that shook around more than the ones I have now. Will be interesting to see if Mazda corrects it. I'm confident they will. There was a similar issue I read about that happened a lot with the CX-9 and even popped up with other Mazda models so it seems to be pretty common for them. Fingers crossed they fix it but so far it hasn't bothered me like I was afraid it would. I do want it addressed at some point though. Seems like it could be a very simple fix for them.