Hi,
Years after, on a different Mac mini (a 2012 Quad-i7) and a different OS (High Sierra), I continue to have the same issue: run dspMixFx, wait a little, turn on the UR-824, and receive the message the audio interface is not recognized. In the meantime, the OS and Logic can work perfectly with it. But I also need the clumsy control panel to remotely set the levels.
After I turn off, then on again the audio interface, it is recognized by dspMixFx. This happened nearly always under Sierra, and happens always since upgrading to HS. I could not solve this issue with the technical support, and am hoping someone with the same problem can help me find a solution.
Best,
Paolo