I just installed a Sony GT250Mp head unit that powers all 4 car speakers. I also have 1 12" JL sub that is powered by a mono amp. Whenever I try to use the aux port or play cds on the deck only the sub plays? The speakers make no sound at all.
Everything works fine when I use the radio. I am clueless as to why this is happening. I have tried the Sub out/Rear out setting and nothing changes