It was an Xbox One controller and Windows 10.
Here's input info from DxDiag:
-------------------
DirectInput Devices
-------------------
Device Name: Mouse
Attached: 1
Controller ID: n/a
Vendor/Product ID: n/a
FF Driver: n/a Device Name: Keyboard
Attached: 1
Controller ID: n/a
Vendor/Product ID: n/a
FF Driver: n/a Device Name: USB Keyboard
Attached: 1
Controller ID: 0x0
Vendor/Product ID: 0x04D9, 0x0269
FF Driver: n/a Device Name: Controller (Xbox One For Windows)
Attached: 1
Controller ID: 0x0
Vendor/Product ID: 0x045E, 0x02FF
FF Driver: n/a Poll w/ Interrupt: No