Dreamcast composite sync & video problem

This is the image with an RGB scart cable, there is no image with a composite cable but VGA works fine. There must be a problem with the composite sync/video signal?

 

Usually this VGA signal will appear like this on scart input because it has double HSync and VSync frequencies, this happened with me before when I was experiment making scart interface from VGA output, what is your question and problem exactly?

 

Did you register just to leave this? I have already asked the question.