Just installed this MTX 404 amp in my car. After hooking it up, with the gains turned all of the way up I hear a loud noise. The RCA cables aren't close at all to the power wire. And the noise is present when the cars off also. THX for the help in advance.
the gains shouldn't ever be more than about half way up. they are to balance line voltages, not meant as a volume knob. they have no effect on the amount of power the amp generates.