I did not find a solution. I don't remember if I tried enabling "both" for the input systems under Player Settings but it would be something to try. I'm glad you posted here because I forgot all about it and I'm starting a new project with Phidgets soon.

Has anyone else tried using Unity's new Input System with Phidgets? I had both a RFID and a HUB with 4 port Relay working perfectly. Then it started timing out on the Open command. If Unity was Open, even the Control Panel couldn't connect to it the Phidgets. It took a while to figure out it was aft...