I had a service call yesterday after DirecTV swapped an HR21 for an HR24. This is the first HR24 i have worked with. All commands worked but the channel +/- and the navigation arrow commands would hit the box and the box would see them as continuous. Example.. I hit channel up and the HR24 channels up forever until i stop it by hitting another button like menu or guide. Same behavior with the other buttons. I learned the new remote and replaced all the commands. Everything worked fine. I just thought it was odd that they have the same hand held remote/layout. Same buttons/commands. But for some reason they changed the behavior of a handful of commands.