Plasmas seem to be more sensitive about having things (Video, DVD Player) plugged into them than the old CRT TVs did, if my limited (to one)experience is anything to go by.
I went to the trouble of lugging the enormous thing back to the shop, and there was nothing wrong with it.....
The LCD I sampled blurred fast motion, so I took that back. Maybe faulty, or maybe what Sawzaw is talking about with smart stretch?