PROBLEM WITH PRESONUS STUDIOLIVE

Hello everyone,
I tell you a problem that I have come to see if someone can help me. I have a table that I use Presonus StudioLive 16.0.2 also as audio interface with the PC. I have Cubase LE 7. Well, while using Windows normally, the sound works, is controlled from the table, etc…
The problem comes when starting Cubase. It usually works with him, but leave Cubase, and no sound. Apparently everything is fine: the driver is, the allocation of devices, but it is like there. Neither restarting. Only reinstalling the driver again Presonus FireStudio.
I have Windows 8 64 bits. AMD Athlon.
Thanks in advance for the help.

Make sure Release ASIO Driver In Background is un-checked in Prefs.