I’ve tried all drivers, talked with Denon support and still have not been able to get a successful connection. Now most recently with this new firmware my unit is freezing in the middle of a event, causing me to restart or use line mode and plug a second laptop into there.
Have you disabled or uninstalled the webcam ? (webcams block MIDI)
Label the USB ports on the lappy - eg: A,B,C & D - not all usb ports connect and power in the same way - so you may find that USB port C works, where the others may not.
Avoid USB hubs - they generally dont work well enough for high traffic continuous data.
Check the lappys settings for the USB ports - no energy saving options - the lappy should not be allowed to power down the usb ports to save power - ever.