In case anyone is still having this issue, I think I narrowed it down to the steering wheel cover. If you tap on the bottom of the steering wheel, it should replicate the buzzing noise that seems to come from the left side of the steering wheel. If you apply upward pressure on the steering wheel cover and then tap, the buzzing noise should subside. I've been using the loop sections of stick-on Velcro circles (not the more abrasive hook side) to slowly correct each rattle in my car in place of felt tape. It adheres to plastic very well. If you fold the circle and stick the folded section underneath the cover, it applies enough upward pressure to stop the rattle. Good luck and may my OCD be with you. Side note: I drove in my boss' new $80k jag and it has sooo many rattles it drove me crazy.
Everyone's car can be different. I have a vibration in the trim or roof area on the passenger side for instance. If I slam my hand against that trim or headliner in that area it goes away. Other trim or parts of my car have a buzz or vibration at different times depending on speed or position of the windows, the panel for the hatch area etc.
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