The right volume wheel on the headset controls the game/chat balance. To use the game/chat balance control rotate the wheel clockwise to increase the game volume and rotate it counter-clockwise to increase the chat volume. When you reach the end of the adjustment in either direction the balance is either 100% game or 100% chat. If you rotate the wheel to the middle so that the dot on the wheel is centered as shown below, the game and chat volume levels are the same.
Once you have found the desired game/chat balance, use the left volume wheel to control the overall volume of the headset.