I have an Alpine head unit in the B4000, and at certain volume levels it will shut itself off. The iPod/CD settings shut off at like 12 volume and the radio at about 16 volume. Any idea on why this would be? I checked the fuse behind the headunit, the wiring is all okay, the plugs are all good behind it, the plugs are good leading to the sub/amp combo I have. Also, I checked the battery and that is fine as well.....any ideas fella's?

Steve