Can you try a different USB port?
Different USB cable (simple printer cable)
Plugging it directly to computer without USB hub
When it is plugged in, do you see the USB logo on the montage screen becoming blue/activated?
Can you try uninstalling Yamaha drivers? The midi audio should still work with less features, in class compliant mode.
Did you update to latest montage firmware?
Latest: montage is usb2, not usb3
Some settings in bios/UEFI may disable the usb2 'legacy' mode
Try to see there the USB settings, or update to the latest bios/uefi
Different USB cable (simple printer cable)
Plugging it directly to computer without USB hub
When it is plugged in, do you see the USB logo on the montage screen becoming blue/activated?
Can you try uninstalling Yamaha drivers? The midi audio should still work with less features, in class compliant mode.
Did you update to latest montage firmware?
Latest: montage is usb2, not usb3
Some settings in bios/UEFI may disable the usb2 'legacy' mode
Try to see there the USB settings, or update to the latest bios/uefi
en ce jour ensoleillé j'imagine dans le sud de la France