I've wondered sometimes just how the RF-capable remotes decide when to send RF versus IR or what color LED to flash. When sending to a TV or AVR, presumably they just send IR. But when sending to a TiVo, do they detect some continuous RF beacon from the box and send RF only if it's present? Or do they always send both and then flash the right color LED only if there is an RF handshake from the box? Or what? Some posts in this thread have caused me to wonder recently if sending both RF and IR commands simultaneously to a TiVo could in some circumstances cause the box to recognize and act upon both signals instead of ignoring the redundant IR signal like it's presumably supposed to do. This could be the result of some sort of timing problem. My 4-tuner Roamio (used only for OTA) has on at least one occasion doubled presses of the Live TV button when cycling past only one of the four tuners, refusing to stop on only that tuner each time around. That surely can't have been a coincidence caused by hardware "contact bounce" or whatever. I wonder if a bit more code has to execute when cycling from tuner 3 back to tuner 0, with the extra millisecond or two causing what should be seen as a duplicate IR code to be seen instead as independent from the RF code which it should have matched, or something like that. Food for thought.