I send my Sky+ RGB feed thru a JS VGA Converter & then into the pw7 PC input. When I watch BBC News (1 & News 24) & they cut to a video piece, I get a black bar down the right hand side of the picture, but not on the left. Even going to zoom setting doesnt remove it. When prog returns to the studio presenter, the pic fills the whole screen. What's going on & how do I stop it? Thanks.