Configuring Xbox Settings:
In order to hear other players you must make sure that the following is set 
from the Xbox 360 dashboard.

1.  From the Xbox 360 Dashboard, press the Xbox Guide button (the X button in 
    the center of your controller) to access your Xbox Live Settings.

2.  Navigate to the "Personal Settings" selection, and press the "A" button on
    your controller.

3.  Select "Voice" from the following menu, and press "A".

4.  On the Voice screen, make sure that "Play Through Headset" is selected 
    for Voice Output selection and that volume is set to 10. It will also work
    on "Play Through Both" however, you might hear an 'echo' effect generated 
    from the voice duplication. 

5.  You can fine tune game audio and chat volumes using the X1 amplifier
    and chat volume controls.
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