Same thing is happening to me and I tried all of the options listed above. Using Overbridge 2.0.30 and Analog Rytm 1.50 with a MacBook Pro and Sierra. Also, I shut down the Overbridge Engine once in an effort to troubleshoot and even after uninstalling and reinstalling Overbridge, the engine hasn’t reappeared; I only have access to the control panel. USB Config is set to Overbridge, Midi Config IO has been set to USB + Midi and just USB. Nothing has worked so far.
This is an older MBP with standard USB 3.0 ports, not USB C. I allowed Overbridge with my firewall settings and no notifications have appeared under the Privacy and Settings control panel.
I’m using the USB cable provided with the Rytm Mk2 and plugging into the MBP directly, without a hub.