Oh I apologize, I can give you some model numbers.
The Xfinity box is a model DC60Xu The Xfinity remote is a XR2 version R1
My Vizio TV is a SV370XVT 37", has 3 HDMI ports The Vizio remote is a VUR9M
I was able to program the XR2 remote to power on/off the tv as well as control the volumne. There's no "source" button which I suspect would be able to shift from cable to component to any of the three (3) HDMI input ports. Don't know how programmable the Vizio VUR9M is relative to the Xfinity box, but it obviously has all the buttons to select sources.
Thanks in advance for everyone's help!
Mike
If God Wanted Us To Watch TV 24/7 He'd Have Given Us Rabbit Ears