Right now I am able to use my headphones, plugged into the headphone input of the AXE I/O, to listen to audio coming from my DAW as well as from the AmpliTube standalone app when I turn the monitor knob to DAW. However, I can't hear audio from any other sources through my headphones (e.g. YouTube or Spotify). When choosing the output device in my computer's audio settings, I can only choose between Line Out 1/2, Line Out 3/4, or Line Out 5/6 (besides the computer's own audio). None of these give me any sound through the headphones (except for sound from Ableton or AmpliTube).
Am I missing something, or am I only able to route my computer's audio to the speaker outputs of the AXE I/O? I want to use headphones to play along with youtube backing tracks. Major oversight if this is not possible.