Tiling / pixelization

​We have had tiling/pixelization since we were notified of Xfinity "upgrading" our service.  We have had two separate techs come to our house.  Xfinity also has sent "maintenance" to investigate outside our neighborhood. One appointment at our house was over 2 hours changing out all connections.  Several neighbors are experiencing the same problems. Xfinity is actually replacing the line of one of the neighbors. Xfinity refuses to connect the dots and fix the problem that is not a house by house fix. Their newest attempt is to send us new cable cards for our TIVO box.  Just kicking the can down the road.  Unbelievably poor service and communication within their own service department.​