Cannot connect a Focusrite to MacBook Pro

[LVanarsdall]

Hello. I am having trouble connecting a Focusrite Scarlett interface, both 2i2 and 4i4 to JamKazam on a 2 year old MacBook Pro. The interfaces work because I was able to have them work on her husband's older Mac. I had the teacher re-install the Focusrite software. I had her change all of her cables. Every time I try do add a Focusrite device, it will see the device, have a presentable latency during the test, but fails the second part of the test and I cannot proceed with the installation. I have tried adjusting every setting that page offers, but nothing I do allows me to proceed. I can setup the internal microphone and use a headset, but I cannot get the device to work. I have done a number of installations with faculty, but this is the first one I can't make work. What am I missing?