The MIDI output can be used for MIDI feedback with controls that support this: https://cdn.eventideaudio.com/manuals/h9000/2.1.12/content/setup/h9000setup.html#midi

Future firmware updates could include some additional features that would be useful with outputting MIDI data, there have not been many requests for this.

Does your last post mean that you have resolved the issue or do you still need help with this?