Could be any number of issues:
- Induced voltage between the head unit and external amplifiers if you have any on the likely RCA connection when it is turned off
- Poor head unit design that does not turn off in an orderly fashion
- Relay issue that is disconnecting the battery before the alternator causing a spike from load dump
and probably 5 things we have not thought of.
- Induced voltage between the head unit and external amplifiers if you have any on the likely RCA connection when it is turned off
- Poor head unit design that does not turn off in an orderly fashion
- Relay issue that is disconnecting the battery before the alternator causing a spike from load dump
and probably 5 things we have not thought of.