ur44 no sound except cubase

Hello everyone.

I bought a new audio interface - Steinberg Ur44 - for my Windows 10.
I installed it as the manual says. When I turn on the interface, the sound is coming out from all of the pc (youtube, wav, mp3 etc).
When I open Cubase 8.5 the sound is coming out only from cubase and there is no sound in the computer . :confused: :confused: :confused:

Does anyone knows what is happening ?

I am experiencing the same thing. :angry: