I recently bought a new JVC radio head unit for my KJ verada. I bought the head unit as well as the required harness wires, according to the instructions from the Supercheap auto guy. I got the old radio out no problem, and once i plugged in the new head unit, earthed it correctly, it wouldnt play any sound. I wiggled, disconnected and re-plugged the head unit in multiple times and still no sound. There was times where when it was connected, it would play the radio for around ten seconds, and then it would switch off and have no sound again. I took it to the Supercheapauto guy,and he had a look and said it should work. He suggested the speaker wires could be faulty or corroded. The head unit and harnesses do work, as they work in my mates 380, so i assume it must be the car. Anyone else had this problem or suggest any solutions i should take?

Thanks