The trailer battery's are 12v. It is not heat because it's not running enough to produce heat. The protection light is on. Is there a way to reset it?
Could there be to much power? When the motor is not running I am getting 12.8 volts and when I am running I am getting 13.8 sometimes 14v.
you alternator should be putting out around 14 so you are fine there
my humble opinion is that your amp is cooked, sorry if i am correct