Ezbus/audio Midi Setup Weirdness, Anybody else experience this? Options

[Levon River]

For some weird reason that is entirely beyond my ken, Apple's Audio MIDI Setup will *not* retain the EZBus as the "Selected Audio Device." It's startin' to get on me nerves.

In the "Default Input" dropdown it has EZbus. In the "Default Output" dropdown it has EZbus. But for "Selected Audio Device" it has "Built-in audio controller" showing in the dropdown. If I drop it down, EZBus is there to select. So I select it (which then opens a whole "Input Section" that wasn't there before I selected it). So I quit Audio MIDI Setup. And *every time* I go back into it, it has changed "Selected Audio Device" back to "Built-in audio controller."

I've tried changing it, then rebooting. No go. I can't find any preferences file that I can trash. So now I'm at the end of my rope.

Does anybody know what in tarnation is going on here and how to fumigate the gremlins?