My microphone won't work in-game?

I’m having trouble getting my microphone to work inside Garry’s Mod. After trying multiple ‘solutions’, I ended up in a standstill. My Steam settings have selected my speakers for my recording device but I can’t seem to switch it back. Every time I try to change the device, it keeps choosing my speakers and headphones over my microphone. Any ideas? http://imgur.com/a/oTntJ <—Here’s what it looks like.

Try setting the right default audio devices in windows and restart. Fixes this in most cases.

The ones I set are my default. I’ve tried restarting a few times already but it hasn’t changed.

Proper drivers for your mic?

Really sure I already have them but how do I check?

EDIT: Checked, I have the most recent drivers, can’t update any further.

I’ve tried restarting my game, my computer, deleting and reinstalling GMod and disabling addons and remounting games. Nothing has worked.