My truck can be totally shut off, key out of the ignition, and it seems to occur after the truck has been sitting for a while. When I open the doors I get some light static through the speakers. (It may occur with the doors closed but I'am not sure on that). Not sure if it is the front only or may be all four. I think it only occurs with the doors open. Also the speakers seem to "pop" when I go to start the truck or shut it off which started the same time as the other speaker noise. I have a Kenmore CD deck and after market speaker installed. No other electrical problems that I'am aware of. Any ideas. Thanks.