Has anyone had a tweeter in the rear door get loose and rattle a bit? I think that's what the sound coming from behind me is but I'm not 100% sure. I asked them to check it out last time I had my car in for service but they said they couldn't reproduce the sound (even though I heard it on the way home after I picked my car up). I'm almost positive it's at least coming from the rear door area. Any thoughts?