SupGuy, the best way to get evidence for violators is to enable your Developer's Console and taking screenshots of the teamkills.
Your console is enabled via [Options] ----> Keyboard Tab ----> Advanced button (lower left corner) ----> Enable Dev Console
This is used with your ~ key.
Open up the console and take a Steam screenshot (my preference) of SoAndSo killed Supguy123 with shotgun. I prefer to wait for multiple TKs to ensure the punishment of ban. Submit the photos with a Ban Request and it will get looked at. Pyro Promises.
As for getting muted, make sure 1) You are not loud into your microphone, 2) your connection isn't buzzing in everyone else's ears, 3) Don't spam.
Hidden is a touchy beta, if you set your microphone transmit volume down from default and close your options menu, the volume will RESET itself at some point. That's why I leave my Options box open and only hit Apply. I'm naturally loud, so I turn my mic down all the time.
Good Luck out there! Beware of Red, EchoChrome, and a few others. Just when you think you're a good player, they'll remind you that you're not better than them
Welcome