Q:  I would like to be able to have it come out of both my desktop speakers 
    AND my headset. Can I do this?

A:  The only way you can do this is by physically disconnecting and connecting
    from one to the other. in order to have a permanent connection to both, 
    you would need an optional accessory as described here:
 
    http://www.turtlebeach.com/products/cables.aspx
    under:
    Surround Sound Splitter Cable

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