Here are the particulars: I have a Phillips Directv receiver and a Series 2 Humax Tivo. I have an antiquated Magnavox TV with a simple RF plug. Now I've hooked up everything and I'm inputting through the Tivo. Everything seems to be working fine when I use the composite, but when I tried to switch out to S-video cables I lose the video. The video cables work as I'm tried them on other devices such and they work fine. Any suggestions?