Discord not receiving mic

Solution 1:

Same problem.

Disabling Noise Suppression on Discord's settings seems to unmute the microphone for some reason.

Solution 2:

In my case, I had a new bar on the top right that appeared once I started discord.

Before starting discord:

After starting discord:

For some reason, every time I restart it, the mic volume is defaulted to zero, so I just need to slide it to an appropriate level.

Solution 3:

Based on Mike's answer:

Set Input Volume in Discord to 100%. Then open Settings -> Sound, Select Input tab and set Input volume to normal (10% for me).

Be aware that if you'll change the Input Volume in Discord, it will reset your Settings!