ProFXv3 mixers let you send audio from your computer to USB 1-2 (Blend Mix) for overdubbing or 3-4 (Main Mix) for backing tracks, streaming, or game audio.
By default, the ProFXv3 uses USB 1-2 when connected to a computer. To switch to USB 3-4, adjust the computer's settings. Here is a guide for USB 3-4 return setup on Windows and macOS.
Some DAWs and streaming apps may have their own settings that override system settings. Please check their documentation if needed.
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