If you hear a whining noise while listening to your car stereo, don’t assume that your sound system needs replacing anytime soon. Car speaker whining can often be fixed without replacing expensive components, like the head unit. However, tracking down the source of the problem can be time-consuming and difficult.
Speaker Sounds Terrible or Doesn't Work at All? Diagnose Speakers in Your Car or Truck!
A common cause of speaker whine is the vehicle’s alternator. If the sound changes in pitch or intensity as the engine RPM changes, it is likely some type of engine noise and interference from the alternator output is a likely source.
The problem is that noise from the alternator is coming through the power cables into the head unit. You can tackle the problem in two ways:
In either case, the alternator will still generate noise, but it cannot travel into the head unit and cause the speakers to whine.
