How do I mute Motorola H390 during COD:4 gameplay on PS3?

[SIREALKILLER]

When playing online on Call of Duty: 4 for the PS3, I noticed that it is an Open chat game where don't press an button to talk. They can hear every thing that is being said as long as my mic is connected. I want to know how do I mute my Headset when I don't want to be heard.

 

[Mitchell]

Just tap the off button and it will turn off then just turn it on when you want to use it again.