Basically, some of the buildings don't stay put in the model as the camera flies through. It's really weird, they stay in the same place in the frame, but not all of them, just some of them. I've tried creating it with a couple different options.
If you go into the Options, select 3D Generation, change your Generator Threads. You might have to play around with the number. I set my to a 10 and my buildings were jumping around like yours. I then set it to a 4 and I haven't had any more issues.
If the issue was resolved by this method, please click on "Accept As Solution" *Civil 3DJ* Todd Rogers
I've seen this issue once before but it's very hard to reproduce. You could try generating your video on a different computer (with different graphics hardware) or updating your graphics driver.
I assume you are using Infrastructure Modeler 2012. Infrastructure Modeler 2013 R2 might solve the issue. We worked on the rendering core and the one time I saw your issue was before our changes. I can't promise though since, as said, the issue is very hard to reproduce.