Special mouse and keyboard keys stopped working

Since my upgrade to 17.10, the following has stopped working:

• Special keys on the keyboard, such as Volume up/down, Calculator, Files, Search, etc..
• Ctrl+Alt+t doesn't open terminal
• Special keys on the mouse; the two back and forward keys on the side

All of these keys always worked all the way to 17.04.

Note: I'm still using Unity, which didn't actually get removed on the upgrade as it said it would. Gnome on Wayland didn't start for me, and neither did Gnome on Xorg after I upgraded my nvidia drivers to 384 (I have yet to try with 387)

What's going on?