How do you make only teamspeak voice come through a headset so the computer speakers plays the rest?

That's a tough one. The fact is all the sound is routed out the output of the selected audio device (soundcard). So in order to accomplish what you're trying, you might require two sound cards - much in the same way you can use dual video cards for two monitors. Mostly, it depends on the applications' ability to select which audio output device to send the signal to.

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