Thanks for sharing your setup. So to summarize, all your I/O is already taken care of via analog or AES, and the USB is just used sometimes? Why do you need the USB audio connection to monitor YouTube videos, wouldn’t you be able to monitor this via your audio interface? I would suggest unplugging the USB connection to your H9000 (unless there is something I am missing where you require this for I/O or MIDI) and give your H9000 a rest 🙂
We do plan on implementing a better way of handling the USB pop-up, but I can’t promise when this will be ready, so unplugging your USB connection would be your best solution for now if it is bothering you.