While playing a game that runs on the Source Engine (Counter Strike: Source, Team Fortress 2) When a player yells into their mic, it creates a loud crackle knows as over modulation.

This is a common technique that mic spammers use to annoy players.
Spammer: HEY!!!GUY!!!!GET!!!TO!!THE!!POINT!!!1!1!!

Player One: OH MY FUCKING EARS!

Player Two: Dude, you've got a really bad case of Source Mic!
by Nope.avi June 29, 2011
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