Cannot get High Sierra Mac to recognize Resident Audio T4, using Thunderbolt 2-3 "Cables Matters" adaptor in LogicProX

I have a 2017 10.13.4 High Siera desktop and am trying to record into Logic Pro X (or Garage Band 10.2) and am not able to get the Mac to recognize my Resident Audio T4 interface. The interface is powered through its tb2 cable and a "Cables Matters" brand tb3-tb2 adaptor. sounds from a mic or instrument go through the interface out to my P.A. and the meeter lights work appropriately. In Midi Setup, the Audio Devices window shows the interface (in a light grey color) but I cannot click on it to make it to use the device for sound input. Resident Audio suggests I delete existing midi drivers (but do not tell me how) and re-installing theirs. I wonder if the built-in mic on this 21.5" has preferences that can be changed so that it shuts off...

I am really frustrated as my band is starting to write and I am letting down everyone by not being able to record anything well.