Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
Most likely this is a complex problem requiring a professional, water seems to be the trigger so I would suspect some sort of rodent damage to the wiring.
Mice are everywhere , regardless of where you live, the issue is a short circuit of the wiring for the radio components not just the speakers but the radio, the amplifier if you have one, and the speakers including all wiring between the components, you have also stated it is affecting your headlights which are a completely different circuit from the radio indicating the problem is very complex and will require complete inspection of all wiring on the vehicle especially where there is a potential for water intrusion to occur such as the trunk ,under the hood ,around all window and windshields. Then you have the chime issue and it will require inspection of the wiring under the dash.
when so many different electrical circuits are involved it usually turns out in my experiences to be rodent damage.
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