Recently my car battery went flat after an interior light was left on. Battery was charged and car starts ok, but since then I've had an issue with my radio and bluetooth. They work fine when the engine isn't running, however when I attempt to start the car the radio goes off and then comes back but I can only hear static on all channels and can't connect anything to the bluetooth. When I switch the engine off and turn the radio back on it is fine again. Grateful on any guidance how to fix this issue!!