I have Comcast basic channels with a non HD box, a Sony av receiver for my 5.1 surround sound, and a Samsung hdtv. Currently I have the rca cords hooked to my receiver because that's the only option on my comcast box. It's giving me audio but no video. I'm not interested in upgrading my comcast box to HD as I've "cut the cords" so these few local channels are good enough. Bought an antenna thinking that would help but now I have over the air stations that play audio through my tv speakers, which isn't ideal. I also have a roku and an Xbox. Looking for help on how I can get those few measly Comcast channels to play video on my tv. Is there a cord to go from coax to something newer on my receiver? the Comcast guy said my setup wasn't allowing the video because all my cords are hdmi. I'm confused any suggestions?