I've had compatibility issues with certain types of tvs with cable boxes. I know Dynex Tv's had problems with HD boxes as well. If the Shaw techs can't figure out the problem on their own box, then my suggestion would be to stick with component cables for the time being as there is no difference in picture quality. Have you talked to anybody on Sony's end where they may be able to assist you? Perhaps it is a quick update or a quick change in the menu.