Join Date: Dec 2013
Location: Sydney Australia
Mentioned: 3 Post(s)
You are going to have to pull it apart.
you need to take the shroud/surround/cover off the headlight and put some thin weather strip foam between the headlight and the surround.
Take a look at the headlight where the surround sits, you might see some wear/rubbing marks where the surround is vibrating and rubbing on the headlight. This is where you want to put a small strip of weather strip.
I had to put some at the top of the city light and my buzzing was gone.
download the service manual from the technical area on this forum and there are pics etc.
While it is all apart you might as well put some thick weather stripping behind the instrument cluster - just in case as this is another source od buzzing down the track.