The 'Options' window ( illustration) lets you configure audio devices for Voice Chat connection mode.
Audio devices for voice chat options window
You can configure the following options:
Lets you select the installed device that will transmit sound during Voice Chat connections.
Lets you select the installed device that will record sound during Voice Chat connections.
At the minimum level all sounds will be transmitted unaltered. At the maximum level, only the voice will be transmitted and all background sounds will be removed.
Set this option to minimum to start, and adjust it only if other users cannot hear your voice clearly.