I changed the fuse in the glove compartment (7 I think) and the two in the rear labeled for the radio. No Nav/no bluetooth. There was some crackling during the first occurrence, no noise at all now. IM not handy with anything but I have a friend who is. I removed the spare tire, there was just a little moisture on the wheel which I believe was condensation due to the recent cold temps. Not sure where the DSP or amp is. Thanks.