@Wonkies, I don't know what console you're on but I've seen posts about Mic Issues for the PS3 console.
I am glad they are muted, I keep them muted so I don't have to listen to swearing 12 yr olds that don't have responsible parents that spawned little monsters.
Yeah! I hate those kids.
I play on Xbox and I set my Communication on Private (only friends can send me messages, talk to me, etc...). The constant swearing and hate mails are just too annoying.