Click wheel doesn't respond to touch

I replaced my headphone jack and hold switch on an otherwise working iPod. After the repair the iPod booted normally. However, the click wheel and buttons do not respond to input. The touch sensitivity seems to be lost and none of the buttons do anything. Toggling the hold switch wakes the display, and the iPod CAN BE RESET by toggling the hold switch then holding center + menu. And the iPod can mount normally; the software seems fine.

Thinking that a connection was loose, I disassembled and reassembled the iPod multiple times, checking everything. All ZIF cables are seated in their sockets. None are broken. The click wheel ground tab was stuck to the framework as normal and taping it firmly in place didn't change anything. Removing and replacing the click wheel didn't help.

I eventually ordered a replacement click wheel and swapped it in. No change.

I noticed that after opening the iPod the first time, one of the plastic tabs with screw holes at the bottom right corner of the case had broken off the face. That corner was a little loose when reattaching the face to the framework. So I superglued the tab back to the face; now the face and framework meet firmly and don't wobble. But the (new from iFixit) click wheel still doesn't respond.

I'm at the end of my rope and disappointed that I may have to scrap my iPod because of click wheel problems that developed after replacing a completely unrelated part (which didn't even involve removing the face or touching the click wheel connections at all!).

Any thoughts?