No sound/weak sound from earpiece

I replaced the frame and lens on my 3gs and during that process I had to remove and relocate the earpiece to the new frame. Upon reassembly everything works except the ear piece. Sometimes I can vaguely hear it but after my last couple attempts to re-seat everything, I've now lost all sound from the ear piece.

The metal cover for the earpiece was slightly tweaked from removal but I've since straightened it out, seemingly without damaging anything, and I can only assume that the prongs on the actual earpiece are making good contact with the gold pads on the underside of the metal cover. Help?