Around 3:21 AM April 30, I was winding down from work and looking at my tablet online. Lights on, quiet, TV unplugged, no other electronics on. I was in bed.A sound best characterized as a blend of flying insect,and electrical buzz permeated the room and was perceived to be moving in front of me, around the room. The amplitude was not soft but quite discernible.The sound then localized at a wall mirror on the left side of the TV stand. The mirror began to move on the two nails that served as its anchor point. The sound stopped as the mirror kept moving.My subjective sense tells me that possibly, this was a directed intelligently controlled event.An examination of the wall behind the mirror revealed nothing. No bug found, no sound.I had the sense to video with my cell phone, but the camera app kept switching off to home screen. Nevertheless I have some footage.I live near the airport in Nashville and am wondering if any unusual aerial or meteorological phenomena occurred.