2 things, make sure that the IP routing is equal in the first 3 places. I believe Comcast (with the surfboard router) defaults out to 192.168.0.1 as the gateway, whereas other schemes might have been 192.168.1.1. If the TV and receiver are set to the 192.168.1.1 system, they will not connect. Either move the router to 192.168.1.1 or hardcode the TV and receiver to the 102.168.0.x IP system.
Next if you are running more than a couple devices, just hardcode all the IP addresses to your devices. For some reason I have found devices like printers and TV's will try to use an IP already being used by another device if they are supposed to be assigned by DHCP. It shouldn't happen that way, but it just seems like it does. If two devices are sharing the same IP, one of them won't work. Hardcoding the devices, although it takes some time, seems to make everything work out better. Again, make sure that you use the same three numbers from your default gateway (192.168.0.x).