Clearing the EPROM-
This may not address the issue below (as suggested sounds like a wiring or maybe hardware issue), but I was having issues with my AOA Pro and the very helpful factory supported suggested "clearing the EPROM" (my paraphrasing). This is done by depressing both buttons, then powering up. Beware- this clears all the current settings you have stored.
Also, the Verification Check List has some helpful tips and instructions (as you have likely seen)..
Regards,
Clark Baker
Legacy- 200hrs TT