Could you provide a bit more detail? What model Roku player do you have? How is it powered (connected to a USB port on the TV or using the wall adapter)? When you change the TV HDMI input to the one used by the Roku, what exactly do you see? If you pull the Roku power and connect it again, do you see the Roku boot screen (dancing Roku logo)? Does the home screen appear, but you just can't control anything with the remote?
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