It's come to our attention that some X3 owners use their headsets for chatting
over Xbox Live only, without having the IR connection to the Xbox active. 
The X3 headset is designed to sense whether signal is being sent from the
transmitter, and not through the controller. If the headset detects no signal 
from the transmitter for about two minutes, it will turn itself off to
preserve battery life. 

In other words, no game sounds will be coming through the IR transmitter 
to the headset, but the Live chat connection from the headset to the Xbox
controller and going out to the Xbox Live network will be active. 

In the above case, you will be using the X3 in place of the stock headset 
that comes with the Xbox 360. 

There is one consequence of using the X3 this way: 

Since there is no sound coming from the Xbox 360's analog outputs, the X3 
will shut itself off after 2 minutes or so of what it "thinks" is no audio
activity. Once the X3 shuts itself off, you will not be able to hear the 
Live chat either. You may think that there is something wrong with the
headset, but that is not the case. They are working as designed and this 
is a feature to conserve battery energy and not a defect.

SOLUTION: 
  Please make sure there is always some game sound being played through 
  the headset, so that it "knows" to keep itself powered on. 
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