WARNING: AUDIO GLITCH @ 3:41
SOMETHING IN MY EDITING SOFTWARE CAUSED THIS, SORRY HEADPHONE USERS!
Using these two programs, Audio-Router and Voicemeeter Banana, you can send your music and stream audio to different audio devices. This allows you to selectively target music playback for either yourself or your stream.
voicemeeter banana: http://www.vb-audio.com/Voicemeeter/banana.htm