Since the TRAKTOR KONTROL S2 does not have any audio inputs interfacing with the computer, the MIC input can not be routed to the TRAKTOR software. Instead, the the microphone and the master output signal from TRAKTOR are mixed directly in the hardware and fed to the MAIN output. Adding a microphone to your performance just requires connecting it to the MIC input and adjusting the level via the GAIN knob on the back of the TRAKTOR KONTROL S2. The MIC signal can not be recorded, sent via broadcast or used as a Live Input in a Deck. 
You can engage or disengage the microphone with the MIC ENGAGE button on the front of the device. The status of the microphone is shown in the microphone indicator below the Browse section on the TRAKTOR KONTROL S2.
