Have you tried performing the Remote Control Setup under the Ray’s settings in the Sonos app?
I don’t have COMCAST cable TV, but I remember that there is a COMCAST remote option to control an A/V system. You must set this option in the remote, otherwise the remote will not send the IR commands required by RAY. During the XR15 setup you’ll be asked to give an A/V model. This is arbitrary, but there may be an option for “SONOS”. Just make sure that there are no competing A/V models within range. After setting up the remote, you can setup SONOS’s response.
