I've had two or more Roku devices, since the earliest iteration. That said, new, unbidden channels began to pop up, on my home screen, in 2008. All three of our devices ARE connected, registered, synched; however, they do not automatically share updates. In the living room, we have sixteen wanted channels, and have just removed sixty-one which had just popped up. In the master, we have twelve--no unwanted pop-ups. And, the unit, in the studio, has never had but four channels. Whomever is moderating, doesn't know the technology.
