MR 816 X quit when Cubase is used

Hi,

I use the MR 816 x on my Mac Pro as my audio interface. On the MR 8816 x is a Roland Integra 7 connected by audio.
When I turn on the MR 816 x and the Roland, de sounds can be hear trough the headphone or the speakers connected to the MR 816 X, and the channels or other settings can be monitored trough the MR Editor.

Now when I open Cubase 7, no sounds can be hear from MR 816 X and the MR editor can not be used anymore.
In Cubase all my settings are as they should be, but I don’t hear any sound from any device connected to the MR 816 X.

Anyone with a solution ?

Thx
Luc