The Stream Mix on the GameDAC can be used to mix together your game, chat, mic, and aux audio and send it out of the Line Out jack. You will have optical connected to the PS4 for game audio, USB connected for chat, and anything else you want to mix connected to the Line In analog jack. Then in the Stream Mix control panel you can adjust the level of the 4 individual channels. The final mix is outputted via the Line Out jack, which you then connect to your PC soundcard's analog input.
What is Stream Mix on the GAME DAC?
