2400mp skips when selecting source

When my 2400mp is hooked up via VGA and it seeks a signal is skips around for several seconds (the pictures hops up,down, left, right)  Is this normal?  It happens regardless if it is connected to my laptop or desktop. 

 

When connected to my projector via a 150 foot VGA I sometimes loose the signal completely, then it comes back, skips around etc...

 

I don't have the same problem with S-video.