Hmmm … strange.
My guess it’s a problem specific to your setup. FF800?
Have you looked at the RME forum?
Sure it can be a combination of things, which triggers a bug in Nuendo. Not saying that there is no problem.
Only thing I know it’s an isolated problem, which makes it pretty much impossible to chase.
The only clue we have for now is FF8000, MacPro and the OS …
Fredo