These steps plus the beta driver listed before made the trick for me (Mac M1 with Sonoma 14.4, August 2024). Thanks!
Thank you !!
Have been struggling with my new MacBook Pro M4 Pro with “No device found”.
Even opened a ticket on Steinberg Support (but so far 10 days without answer)
Your guide solved my problem and finally I can work with my UR816C in Nuendo 13 