Are you running off the factory radio, or an aftermarket radio?
It sounds like you've tapped into the wrong wires if you are off the factory radio for your line output converter.
If you are off an aftermarket radio, then something is...horribly wrong. Little more info and we can get this sorted out.
^x2. The amp would be located behin the rear driver side panel on the cargo area. You shoul be able to peek through those vents and see it if ou even have one. I didn't have one
05 Jeep GC WK, 3.7L, SCT programmer, K&N CAI, FASTMAN ported TB, Flowmaster Super 44 cat-back exhaust (Dumped), HD Bilstien's, 6000K HIDs, 5% Tint ALL the way around, Full Infiniti speaker system with an Alpine HU, TOBY Subwoofer(THE GREATEST), Plasti-diped Rims