fuuuuuuuuuuuuuuuuuuuuuno there independent of each other I ran into that issue awhile back with my hu it only had one sub out you may be able to open it up and solder two wires on in there run them out and solder them to the rca and heat shrink it for now until you get a replacement rca jack
How did you run yours, I ended up going to radio shack and getting a splitter and if you pull one channel on the amp it will continue playing but at half power.I know my Alpine PXE-H650 has only 1 rca output for the subwoofer. //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif might work