I've installed a 500/1 using stock deck and a navonne converter.. pushing a ten inch rockford p3 in 4080's box.... how should i connect the rca's on the amp and should i have the amp input selector in high or low position.. also if i put both the rca's on the amp at the same time.... the sound is barely there as soon as i disconnect one, it thumps... anybody know why this is and do you think i need a y adapter... anyways any help would be great... thanks

 

Input selector to low input. Check your wiring, you may have 1-channel wired out of polarity and therefore out of phase which is causing the cancellation when both RCA's are plugged in. Good luck.