Philips Flat tv question

I have a tv from Philips, model #20pt5441. I cant seem to get the AV channel to switch from SVHS to any other. I want to use my Xbox 360 on it but it never displays a picture, just sound. Everything works properly,the 360, and all ports. I just cant figure out why the picture wont display. HELP ME! The philips site had no answers!

If it helps, I use to have a dvd player running to the S-video input but I took it out. I think it may be looped to go to the S-video AV channel, but I cant clear it!