I have an old Panasonic cassette deck.Using a pyramid 240 watt 2 channel amp,and used 12g wire on both the hot and ground wires.
The rca patch is about 6 feet long.Not much length left over.
The power wire is connected directly to the battery,as in clamped in the terminal with the positive cable.This usually solves the alternator noise for me most of the time.
The amp is under the left side of the seat,and the sub is under the right,maybe the problem is with this.
Like I said I have used this whole setup in the other truck without issue.Maybe it's a sign to buy a CD player
