Are you running Cubase 7 in 32 Bit or 64 Bit? In case you run it in 32 Bit, please try the same in the 64 Bit version and let me know if the problem persists or not.
Best wishes,
Jörg Hüttner
I'm running Cubase 7 in 32 Bit. I can't run Cubase 7 in 64 Bit as some plugins are not compatible