New users added as admins, then auto banned? What?

[obglobal.net]

I made a thread prior to this one, but it got all convoluted. This thread explains the process more clearly.

- New users are added as admins instead of registered users.

- Then they're automatically banned.

- I disabled all hooks in my config.php and the issue remained the same. *I registered myself.

- The new users added as admins do not show as admins under the usergroup manager section.

- After changing these new admins to registered users, they're able to use the site as intended.

So the issue is that for some reason, these new users are being registered as admins, and I need to find a way to stop that from happening. It's a real shame, because my forum's been somewhat slowed down by its focal sports team's terrible play this season.

Any help is much appreciated. Thanks very much.