Strange constant buzz from speaker, continues on, even with no key in the ignition
So Its been cold out lately, single digits, and I go to may car in the parking lot and press the button on the fob to open the door, immediately I hear this constant buzz that was coming from the drivers side speaker on the rear parcel shelf. It was loud too, I could hear it with all the doors/windows closed from outside the car. It was like the car was possessed. I turned on the radio and the buzz kept on going in the background over the music. I shut off the radio, turned on the ignition, shut off the ignition, pulled the key out and only after several lock/unlock cycles did the noise stop. Speaker sounded fine afterwards so it's probably not blown. To me this seems like some an electrical gremlin not caused by the radio system, just manifesting itself through that left rear speaker because it started immediatly after I unlocked the car for the first time and didn't resolved itself until after a few cycles of locking/unlocking.
Anyone else have this happen?
Speaking of rear parcel shelf, when driving over bumps in the road, I have been getting a lot of creaking and/or ticking from that area since the weather has turned colder and the colder it gets the more frequent the noise. If I get that buzzing from the speaker again, I will take the car to the dealer and do a 2fer and have them try to resolve the noise in the rear shelf along with checking on the possessed speaker.
2008 E90 328i - Sparkling Graphite/Terra/Dark Burl, 6MT, Sport, Premuim, Fold-down seats, iPod/USB(6FL). M-Sport Steering Wheel, ZHP M-Sport Shift knob, Euro fog lights. Euro Split Armrest