iPod click wheel will scroll but not click.

I recently replaced the logic board on my iPod class 160GB. I reassembled it, and at testing found that the click wheel would not work at all (no scrolling or clicking). After taking it apart again a few times, attempting to reconnect the click wheel, etc. I figured the click wheel must have a problem, so I ordered a new one and installed it. Now, the scrolling works on the iPod but it won't click. The click wheel makes the same satisfying clicking noise when you hit the buttons, but nothing happens on the screen, which means I can't even get past the language choosing screen :(

Everything else seems to be working order... as I understand it, the buttons on the logic board are what allow you to click, suggesting a problem with the logic board. But after replacing the click wheel it scrolls, and this is a brand new logic board. All other logic board operations seem to be just fine.

If possible I'd like to avoid ordering a new logic board because they're expensive... and because I'm not sure it would fix the problem. Could it be the logic board I got had faulty buttons on the front, but the rest is working? Do I have to order a new logic board? Any advice would be helpful in troubleshooting the problem.