Instructions
Reduce the volume on your television and the headset to remove distortion and unwelcome outside noise.
Disconnect and reconnect the headset to the headset port on the underside of the Xbox 360 controller.
Check the voice settings on the controller. By pressing the green and silver Guide button, enter the Voice option listed under Settings and Preferences. Check if the Mute option is checked. Uncheck the Mute option, raise the volume to 10 and select the "Play Through Both" option.