So I purchased my jeep with a aftermarket head unit in it. 2014 jk Rubicon with factory sub. I'm trying to sort through what I need to do to wire the amp for rcas. Reason when I'm on the head unit trying to tune the settings for the sub nothing changes. When I switch to settings for front speakers the sub changes its levels . It seems the current install runs the sub and fronts together. I'd like to change it if all possible. I was told he had it installed through best buy.

 

You will have to do some wire tracing and see where the sub wires go. From what it sounds like is they didnt know how to run RCA's from the head unit to the stock amp and just tied the sub wires to the front speakers. You might have to pull the head unit and find the sub wires in the harness and get a set of RCA to speaker wire and go from the SUB out RCA's on the head unit to the wires going to the amp.