PLEASE MAKE SURE THAT YOU ARE USING A SET OF FRESH BATTTERIES!
This article is especially recommended for those of you with more complex
setups.

If you are not hearing the game soundtrack, here is an easy way to test 
to make sure the X3 transmitter and headset are working. You will need 
the following items to perform the test:

1) A portable MP3 player, CD player or other stereo music player
2) A (known to be working) Stereo Male-to-Male 3.5mm (1/8") audio cable with
   mini-phone plugs at both ends, as pictured below:

  

- Turn off your TV.
- Plug one end of the audio cable into the MP3/CD player's Headphones jack.
- Plug the other end of the audio cable into the Ear Force X3 transmitter's
    LINE IN jack. 
- Make sure the volume is up on the transmitter (rotary dial on the
    transmitter's back panel).
- Play a track on the MP3/CD player. 
- Stand at least 4 feet back from the transmitter, but within line of sight 
    of the transmitter. 

Do you hear the music? If so, then your X3 headset and transmitter are
definitely working and you should be able to hear playback of the game
soundtrack from your Xbox. 

Next, turn the TV back on. Does that interfere with the X3's IR transmission? 
- If your audio playback sounds normal, then you should have no problems using
    your X3 setup with your TV. 
- If the audio playback now has hum, a higher level of hiss, or sounds
    garbled, then we now know that your TV is interfering with the X3's IR
    transmission. 

If that is the case, then you may not be able to use your X3 with that 
particular TV. If the headset plays CDs or MP3s OK, then you know it works 
for audio playback and should work with the TV -- unless the TV is sending 
out an electro-magnetic field that is interfering with the headphones' IR
transmission. 
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