Pioneer CLD-97 + Demodulator - Need Help

Hi all from brand new member. I have had a CLD-704 for some time and have just bought a CLD-97 a few days ago as I have always wanted one. The one owner unit seems to work great but sometimes when the movie starts and occasionally during , the picture will look as if it is fading off on the right side or acts like a phantom wiggling sometimes with a black line. If I scan back and play again it does not always happen. It seems to be random. Also on a disc I played which is only in good condition the picture seemed to want to go phantom on me a lot as well but plays fine on my 704. I do not think it's a problem with the unit but am unsure as I have never experienced this with my 704. What exactly is a Demodulator and is it meant to fix this problem? I am not an electronics guru and much of the tech talk is over my head. Thanks to anyone who can help.

The problem has disappeared and the unit has not given any more trouble. I do have another question regarding hook up. My hook up is very simple, LD video out by S cable direct to TV (old Sony projection 52") LD audio out to AV receiver. TV speakers not used. Sometimes regardless of LD player hooked up the picture suddenly disappears and the "Video One" comes on the screen, sound still fine. If I turn off the AV Receiver and then back on the picture reappears. This happens randomly and does not make any sense since the video does not go to the AV receiver at all. If you or anyone else can explain this mystery I am all ears and thank you in advance.

Thanks Kurtis I'll check that out. Since the same things happens if my 704 or 97 is hooked up it' probably the cable. I'll change it out. Thanks again.