S3222HG, can't get into OSD menu?

Hello,

I'm trying to get into the OSD menu of my S3222HG and I just can't. Every button on the back panel just brings up the input source selection, pictured below. From there, I can't back out to any other menu. I can navigate and select an input source, but that's it. Every button otherwise either backs out or selects the highlighted source.

The only other thing I can do is open up and navigate the lock menu.

So ultimately I can confirm that every button is functional in that it does something when pressed and that all four directions on the joystick are working when in a menu that features a vertical or horizontal set of options.

This was not happening when I got the monitor several months ago. When doing my initial setup I had no problem going in and tweaking all the settings for general use. I want to say I setup some of the buttons as shortcuts, but that shouldn't keep me from accessing the general menu from pressing the joystick. I've tried the usual: Disconnecting all input sources, power cycles, unplugging from the power. Going through the manual, I see no sort of physical fail safe for a factory reset or anything. Everything in the manual wants me to get to something in the OSD menu. Please tell me I'm just a dummy and am missing something obvious.