Hey guys, ive got an aftermarket Blaupunkt system in my car thats powered by a 4ch amp in the trunk, ive noticed lately that im getting the sound of the alternator through my speakers, it didnt do this before, any ideas?

 

A stereo system needs a little regular maintenance. Check that you grounds are tight and rust/corrosion free, that your battery terminals are clean, and the water level in the battery is full (if serviceable)