Absolutely not. We do NOT need this.
First of all, NO ONE IS GOING TO MUTE OTHER PEOPLE. That will be the biggest leading cause for bans and drama.
Let's say a guy mutes the admin, and the admin is asking him to do things. That guy will then be banned, without him even knowing why he was banned.
Muting doesn't solve things like on your little
Black Ops (Call Of Duty)
Those are random people you could give a stuff about. These are Blocklanders who join your server, most of which you are friends with. We don't need to provoke people to be even more of a jackass towards others.
So once again, just because you say "Mute button" doesn't justify the whole thing. Next, there will be Mic-only servers, preventing anyone from a mic from joining without getting banned/kicked.
Blockland is fine just the way it is. If you aren't autistic, you can download many programs, such as Skype, which support voice chatting...