Not work direct monitoring in Mac os x

I use in my studio Nuendo 5/RME Hardware/Mac OS X, but I don’t know why direct monitoring stopped to work. I need to help because i can’t work without direct monitoring. If problem with Direct monitoring unsolvable, I’m ready buy to new device MR816, if direct monitoring will be activated.

Check your RME-HDSP mixer settings.
DM is “handled” through your RME software:

I have a question about MR816:“if i’ll be use MR816, direct monitoring will be activated in Nuendo?”

Direct monitoring doesn’t work in OSX, except for the MR816 series.

Thanks for the answer. Sincerely, UrfunDjuce.