PTFirst won't recognize my MBox 3

[Ormond]

I am running El Capitan 10.11.1 on a new MacBook Pro. The blue light on my MBox keeps blinking. Won't go steady "on" like in does in my PTLE8 program. I go to SetUp>Hardware and the best I get is Built-in Microphone or ProTools Aggrregate I/O. If I choose External Microphone I can talk and PTFirst records my voice....SO, PTFirst is working but my MBox is not recognized. And yese, I checked under System Preferences and MBox is installed.
I HAVE INSTALLED THE LAST DRIVER FOR THE MBOX OSX-1.2.3 - MBox control panel says "Hardware not connected."

I have searched the question database - no answers. I would think if any hardware setup would be seamless it would be with Avid's own hardware device. What am I doing wrong? If the MBox was supported in Yosemite I am sure it would be supported in El Capitan.