Solution for Um-One not working with Mac shown at the *** below
I just tried mine on an MBP and had the issue where the light didn't come on.
I checked the toggle (Comp/Tab) and it was set properly (set to Comp).
I checked direct connection to all the USB-C ports using the Apple dongle.
I checked System Information App (in Utilities) and the Um-One did show up under one of the USB ports. Note: you have to restart the System Information App if you unplug or plug while the App is on.
***I opened Audio MIDI Setup App (in Utilities), went to the Menu->Window->Show MIDI Studio and when that window opened I clicked on the Um-Ones there and the light turned on the hardware (it may turn on as soon as you open MIDI Studio as well). I clicked on the little Keyboard in the toolbar to Test the MIDI connection and then the down arrow on the top left Um-One and the "In" light on the Um-One hardware flashed indicating MIDI being received by the Um-One. I confirmed it works through my USB Hub as well.***
Hope this helps!
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