Incorrect Install?

I've just installed a Basslink in an Escape and used a RCA converter to tap into the speaker level wires. Now when I run the speaker the output is really low. When I unplug one of the RCA's at the speaker (doesn't matter which one), the output like triples. I didn't ground the RCA converter wires to the head unit per the instructions...is this my problem? I think the directions said that if there isn't sufficient output then they might need to be grounded but I no longer have the instructions (figures!) There wasn't a right or left on the RCA converter so I thought maybe I needed to switch the inputs on the speaker and that's how I discovered the increased output when I unplugged it. If anyone could please post some input here I would appreciate it. This is my first car audio install so any newbie tips are appreciated.

you probably have the convertor wired out of phase, try cutting1 set of the speaker inputs to the convertor and switch the ploarity (the + and - wires)My mechanic told me, "I couldn't fix your brakes, so I made your horn louder"