Audio crashes when i close the midi editor?!?!?

Hi Guys,
weirdest thing…
When I edit any midi and then close the editor in the lower zone the audio engine dies…
Then if I try to revert or close Cubase pro, it freezes… I have to kill it in task manager
I am on windows 7 .


Do you use MIDI Tracks, or Instrument Tracks? What is the output of the MIDI Track?