Problem getting rear seat (passenger side) to fold down

I was installing XM radio this weekend and ended up mounting the antenna on the trunk. I needed to fold the rear seat down to route the wire to the tuner. I originally wanted to come in on the passenger side, but I couldn't get that half of the seat to fold down. Yes, I inserted the key and turned it to the left for that seat, but it didn't release. Turning the key to the right released the other half of the seat no problem. Is there something I'm not getting here? I didn't spend too much time fighting it, but now I'm considering replacing the rear deck speakers and I hear that the entire seat (among other things) must be removed to do this. Anyone else had a problem getting your rear seat(s) to fold down? Any suggestions on a fix? Thanks in advance.

Did you try pulling the handle in the trunk?

ya, there is a little black handle under the rear deck, in the trunk. Pulling that rear deck off is a pain in the ass, just to replace speakers. Yes, you have to take the seats and the side panels out. It could take anywhere from half an hour to an hour and a half. depending on how easy it is for you. when you change the speakers, u have to cut the oem connector off and splice the wires that come with the speakers. just letting you know.

or when you install the speakers they do sell the oem adapters so you do not have to cut the plug so if you decide you dont want the car just plug the old speakers in and no problem