Download and install:

  - http://vmpk.sourceforge.net/#Download
  - https://www.tobias-erichsen.de/software/loopmidi.html

On loopMIDI:

  - Check the + in the Setup tab to create a new port

On vmpk:

  - Edit -> MIDI Connections
  - Uncheck “Enable MIDI input”
  - Under Output midi connection select “loopMidi port”

On AudioPluginHost:

  - Options -> Change Audio Device settings
  - Check “loopMidi Port” in Active midi inputs