ASROCK B75 Pro3-M User Manual page 4

To enable Multi-Streaming function, you need to connect a front panel audio cable to the front
panel audio header. After restarting your computer, you will find "Mixer" tool on your system.
Please select "Mixer ToolBox" , click "Enable playback multi-streaming", and click
"ok". Choose "2CH", "4CH", "6CH", or "8CH" and then you are allowed to select "Realtek HDA
Primary output" to use Rear Speaker, Central/Bass, and Front Speaker, or select "Realtek HDA
Audio 2nd output" to use front panel audio.
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ASRock B75 Pro3-M Motherboard