FWIW, I tried to plug the ARP directly into the Synthstrom Deluge using USB-B to USB-B (Deluge can power ARP if it's plugged into 9v cent neg power at the time), and it could not 'learn' the ARP on any channel. Seems to work fine with DIN to DIN however. I don't think this is isolated to just the CME hub since plugged directly into the Squarp Hapax I could not reliably send or route any note data from the ARP either. Likewise, DIN to DIN just works in this case as well. Thanks!

Hi Chris, It is indeed the H4. I'm using the USB C port to monitor and update routing from my Mac with the powered hub on the USB A port of the H4MIDI WC. And correct - If I plug the ARP into my iPad using the device port I can route and use it with AUM and AUv3 instruments yes. I just can't get it to connect to hardware synths directly or indirectly using the USB host or device ports so far. Thanks