HD | Native card not recognized by Catalina?

[gtomassetti]

Hi:

It's been quite a long time since I've been on the forum, and I know my info is out of date. Both the desktop and laptop in my equipment list have since been swapped out.

Main computer: Late 2015 iMac, 32 GB RAM, 1 TB SSD.

PT 20.5.0.207

For the past year or so I've been using my Omni/HD Native in a Sonnet Echo Express III-D Thunderbolt 2 chassis, with no issues at all. When my Metric Halo ULN-2 recently developed problems, I made the Omni my default audio I/O without any glitches.

I finally decided to upgrade to Catalina, since it appeared that the compatibility I needed was there. One thing I checked was on the Sonnet web site, which indicated that even though the Echo Express III is discontinued, it's Big Sur compatible, which made me assume that it would be Catalina compatible as well.

The problem I've run into is that the computer system does not see the Omni. I have a PCIe SSD in the Sonnet which the system does see, but if I open Pro Tools, there's no indication that the Omni exists at all.

I've restarted multiple times, power-cycled the Omni, and tried connecting the Omni to the DigiLink 2 port, with no success.

Does anyone know how I can get things working again, or am I going to have to try to roll back the system to OS 10.13 or 10.14?

Thanks very much for any advice.

Gary