my mic doesnt work?

everything is turned up to max but i am still quiet when i try to play in game? even my mic volume in game is all the way up/ im running windows vista. any help please

Right click on the volume icon in the bottom right and go to recording devices make sure your microphone is the default recording device.
If it is, go into properties and check the "levels" tab and make sure it isn't muted.

its all unmuted adn it is default its just quiet