Cutting sound from a individual unit

[fragsta]

Is it posible to make a unit make not sound like a helicopter be silent like they do somehow on some news channels? like u could type:

"heli1 silent"

or something! Help ne1? thanx in advance!

[SH@dow 113]

Indeed a good quistin, can't help whit that  but i also need tha awnser  :-\