I've had a buzz since new, its not always present, but usually shows up while I'm cruising on the freeway over rougher pavement.

Haven't been able to pinpoint the location yet, the sound seems to be coming from the lower part of the drivers side A-Pillar close to the side mirror adjustment nob. Strange part is that if I apply moderate pressure to the top of drivers side door armrest storage bin, the buzz will get quieter or go away. I've removed the contents of the bin and even while empty the noise can occur.