Microphone Dampening

How do I turn off sound dampening on other's microphones? I'm trying to play TTT but everytime I talk on my microphone it turns down everyone elses microphones down to half volume until I'm done speaking. I would like to turn this off, I don't need to hear myself talk so much that I need everyone else to turn down and it just makes it more difficult to hear everyone.

tl;dr How do I turn off Microphone sound Dampening?