Are you using an adapter of any sort between the monitor and computer?
The -1707 is very rare - its when an AppleEvent is called, but the action is not actually an AppleEvent (very basic rundown).
AppleEvents are what the MacOS is based around - moving, copy, clicking, are AppleEvents, etc, I think... I can't really remember.
Try reinstalling QuickTime 4 (remove 5 by hand), and see if the error goes away...