I have an M-Audio KeyRig49 midi keyboard controller connected to my iMac running OS 10.15.2. I added it to the list of external devices but Studio One 4 tells me that the keyboard is not connected. It is connected and works fine with other audio applications such as Sibelius or Garageband. I have uplugged and plugged in the keyboard several times with no change. Setup: 2019 iMac, Agogee Element 88 and Studio One v. 4.6 with PreSonus Faderport 8 control surface.