This post provides some info I've discovered while troubleshooting the AX8 when connected to a new model MacBook Pro equipped only with USB type C ports.
USB-C ports require an adapter to connect to the USB Type A-B cable needed for the AX8. These adapters can be very finicky. In particular, the order in which you make connections seems to be critical. To resolve connection problems, please connect the adapter and cable to your computer FIRST, then connect the USB cable to the AX8. If you connect the cable to the AX8 first, it may not work when you connect to the adapter and then to your computer. You may also need to reboot the AX8 or the computer after having any problems.
I've reported this to Apple. If this is a bug in their hardware or software, I think they'll be likely to address it.
If the above technique does not solve your problems, you can try another one that has worked for some others. On both Windows and other Mac computers, some third party USB drivers may also cause problems for other devices. These manufacturers care only that their own products work. On the Mac, physically disconnecting other audio/MIDI devices and then creating a new CONFIGURATION in the MIDI STUDIO Window of OS X often solves problems caused by 3rd party drivers.
USB-C ports require an adapter to connect to the USB Type A-B cable needed for the AX8. These adapters can be very finicky. In particular, the order in which you make connections seems to be critical. To resolve connection problems, please connect the adapter and cable to your computer FIRST, then connect the USB cable to the AX8. If you connect the cable to the AX8 first, it may not work when you connect to the adapter and then to your computer. You may also need to reboot the AX8 or the computer after having any problems.
I've reported this to Apple. If this is a bug in their hardware or software, I think they'll be likely to address it.
If the above technique does not solve your problems, you can try another one that has worked for some others. On both Windows and other Mac computers, some third party USB drivers may also cause problems for other devices. These manufacturers care only that their own products work. On the Mac, physically disconnecting other audio/MIDI devices and then creating a new CONFIGURATION in the MIDI STUDIO Window of OS X often solves problems caused by 3rd party drivers.