Down Arrow only lights up Undo Seq button

I'm definitely a new MPC user, but I think either something's wrong or the button was remapped somehow. The down arrow on my MPC 1000 doesn't do anything but light up the UNDO SEQ button. It doesn't function as a down arrow on any screen.

I thought maybe the OS was just hosed, so I tried to install the latest version 2.11. During that install, everything works fine (CF card, connect via USB to computer, transferring BIN file). But, when I power up while holding the WINDOW button, it simply starts up and does nothing. Pressing the record button after again does nothing.

I've also tried restoring factor presets (Powering up while holding ERASE), but again, same problem.

I'm thinking something is just off with my Window, Down Arrow, and Undo Seq buttons. All other functions on the MPC seem to work just fine.

Any suggestions on what I can try before sending back? Thanks for the help.

FYI...I never could figure out what was wrong (neither could anyone else), so I swapped it out for another new one that is working like a charm.

I have the exact same problem, I'm just not sure how to fix it.