I have a dvd sony model DVP-NS300 that I want to connect to my comcast cable. I have a GE TV with no audio/video RCA jacks, but I do have these on the back of my Comcast box. In coming cable signal is going to box and then out of box to the TV. Can I use the audio/video on the cable box to complete setup? I have the large comcast box which also has the s video cable connection. I don't see a setting on dvd to set the channel either? Thanks..