Video during recording in Sonar PE 8

Hi,

I'm working on a short cartoon, and I have strange reaction with the video.
When I record in real time with my MIDI keyboard, the video is NEVER at the good place, for ewample, if I plan to record from measure 75, I see the video showing pictures that should be on mesure 100 or 110 !!!

The strange thing is that if I record in Step-recording, there is no problem, and as soon as I hit a key, a new picture is going on.

Did anyone have this problem ?
What can I do ?

Maybe I didn't select something in a menu.
I'm not used to working with video, that's the first time.

Thanks
Alex