I have the same problem with my MR816s. I brought this to Steinberg’s attention months ago. Their customer service is really the worst. All they ever do on my tech support calls is "documents’ problems; but they never have fixes for anything. The only “fix” is to change the buffer size in the MR utility program, then reboot the computer. Look in the program folder for your interface. There should be a “utility” folder. In there is a utility program that adjusts the buffer size for the interface. Small, medium and large are the options. I switch back and forth between small and medium. Start your computer; run the utility, change the setting and close the program. The reboot. The hardware dropdown will return. The catch is - it only works once! The next time you exit Cubase, the problem reappears. So you have to go through the process every time.