Our SEL started with the buzzy noise around the sun roof. I took a look in there and there is a plastic frame that goes around the opening in the headliner, presumably to stiffen the headliner. Anyway, what looked like hot melt glue that was holding the frame to the headliner was not holding. It still had some tack that would give you a stick noise when pressed together.
Anyway i ran a bead of silicone RTV adhesive between the frame and the headliner and it has been noise free for the past couple of months.