[Darryl Ramm]

The DigiLink license is (was) only used by Pro Tools Ultimate so no it cannot be that. And even if it could be it’s not going to block inputs but not outputs.

Your support plan has nothing to do with drivers working or other DAWs.

What *exactly* is showing up in Audio/MIDI setup Audio devices?

edit: Unfortunately there has been a rocky time for HDX driver issues on macOS but I am surprised that the problem here is no inputs working (vs. not working at all which would be more likely at least to me). With the "microphone" issue being the obvious thing I can think of, and great you have excluded that. And sorry for the "dumb" question but you're sure the output you are getting is from the HDX not some other interface that might be connected into your gear? (I ask because I've done similar, at least with Pro Tools with will randomly picks my monitor controller USB input as a playback engine @#$%).