AEware Remote Troubles

My AEware remote has stopped working and I'm struggling to troubleshoot the problem. My original setup was a Kenwood KDC-225mr and the AEware TSC-55 (this one: http://www.aqua-man.com/mmAM/images/row_num/92735.jpg).

I confirmed there's continuity from the remote to the blue wire on the back of the stereo. I confirmed there's power to the remote. I checked the voltage on the blue wire while pressing buttons on the remote and the voltage decreased in conjunction with the button presses. Since this wasn't working I decided to start replacing components next.

I bought the OEM replacement AEware remote (this one: http://www.geckoalliance.com/lib/ima...75_produit.png). Still no luck. So I bought a used replacement head unit with a factory installed remote wire (KDC-MP638U - images of rear side: http://images.sonicelectronix.com/im...u_kcabt100.jpg). I spliced the original blue remote wire to the blue remote wire on the new head unit. Still no luck.

I'm not sure what to do next. Is there a different head unit I should try? Any others ideas on troubleshooting?