Mac connecting with USB C-What am I doing wrong?

Hello community!

I have two Tone Boards and I’m having the same issue with both. I am trying to connect from my MacBook Air to the Tone Board vis a USB C double ended cable (not the one that came with the Tone Board because my computer does not have an “old school” USB jack.

I do not see the Tone Board selectable as an output device. What am I doing wrong?

Thank you,