I think he recently added it, since we asked. If the noise is coming from the ODO area, it could be the mirror. A few have posted that it rattled, and had wedged something to the top of it to keep it from moving. By the way, I am not referring to the rear or sideview mirror. The speedometer image is a reflection, thats why it appears to be deeper.
Actually I finally figured out that the buzzing sound I was hearing was coming from the rear view mirror. No wonder why it sounded like it was coming from the passenger side when my passenger said it was coming from my side! It was coming from the middle! Now all it takes is a touch or two and the irritating buzz goes away
Do you have EZPass, or whatever they call the auto toll paying system over there, on your windshield? I have a suction cup mount for mine, holding it at the middle top and middle bottom. The right side hits the windshield and resonates with vibrations. I am going to put padding at the ends.