I have just had a projector fitted and when I watch video the screen shimmers. If I stop the video and just watch the TV through the video it is okay. If I record that TV and then playback it shimmers. I can take the video to another machine and the recording is fine. I have swapped the video machine and that has the same problem although I seem to have a morie pattern with the other video. My CRT has a line trippler, could this be a resolution problem, should I call the installers back?