Not familiar with this remote. How does it connect to your TV normally? Is it Radio Frequency (RF), InfraRed (IR) or Bluetooth (BT)? The Sonos you have can only use IR to receive commands, but it uses the same ‘code’ as your TV, and ‘learns’ the IR, rather than having its own ‘codes’. 

Thanks Bruce. I did everything I could, looked at a bunch of vids and nothing. This is a widely used remote from xfinity but nothing. Finally, in the Sonos app, I found an instruction that had me point my remote to the sound bar then toggle the vol up button 3 times, toggle vol down 3 times, the toggle mute 3 times and bam sucka! It works! Thanks for the concern, much appreciated.