I had been using powerline ethernet and could stream both SD and HD, but frequently had problems with the two Tivos seeing one another. I had Cat6 cable run to the bedroom and the living room. At the router end both cables terminate the router. The other ends terminate at a gigabit switch. The switch connects the Tivo plus a PS3 and the TV. The to Tivos could see each other immediately and I could stream SD with no problem, but HD stuttered like it was contently buffering. Netflix worked fine as did the PS3. Tried different ports and new patch cables. No change. Tried various combinations including plugging the Cat 6 cable directly to the Tivo. What worked was bypassing the switch in the living room but retaining the switch connection in the bedroom. Now HD streams in both directions. Is there a problem with going from one Tivo through a switch to the router, through the router to another switch and from there to the other Tivo?