✅ Fixed
Aftermarket stereo electrical issues: ALTERNATOR WHINE (alternator noise in speakers): ground loop. Run dedicated ground wire from head unit chassis directly to battery negative. BATTERY DRAIN: always-on wire connected to ignition-switched wire — head uni
Aftermarket stereo electrical issues: ALTERNATOR WHINE (alternator noise in speakers): ground loop. Run dedicated ground wire from head unit chassis directly to battery negative. BATTERY DRAIN: always-on wire connected to ignition-switched wire — head unit draws power with car off. Fix wiring. AMP CUTTING OUT: under-voltage — too much load for stock alternator, or undersized power wire. Upgrade fused power wire. BLOWN FUSE: wrong amperage fuse installed. Always use correct gauge wiring for current load. 12 gauge for up to 20A, 10 gauge for 20-30A, 8 gauge for amplifier runs.