I don't think you understand. If we can find out which protocol and device number your TV responds to, then we can assign an Extended Function Code to each button on the remote (nearly any of your remotes) so that the remote sends the correct IR signals to the TV to make it turn on/off Ch+/-, menu, etc.

It is much easier to do that if we are quite sure about the protocol and device number. It helps us to figure that out if you tell us which setup codes on which remotes get any kind of a response from the TV.

At this point, I think you have said that setup code 171 on a URC-4063 controls power and volume.

I think you have said that an unidentified Comcast remote, using an unmentioned setup code controls power but not volume. Please tell me if the Comcast remote has a red Select/OK button, and if it is silver.  Actually, look at www.urcsupport.com/index.php and tell us which picture most resembles your remote.  Also tell us which setup code you used.

If the Comcast setup code was 0171 (or 10171 with a red button), then the results are hard to understand. For those setup codes, the 4063 and typical Comcast remotes send the same IR signals for volume and power.