Does that happen Before or During your game is running?
By this I mean, did you plug in your USB headphones Before launching your game, or while it is running?
If the latter [while] Then restart your game, and ensure you have the latest drivers, and have the appropriate settings in the Sound Control Panel...
Hope this helps...
If it is While, you could attempt to reinitialise the sound card for the game... But after some digging, I have failed to come up with anything... Let us know what scenario you are experiencing this with...