Do you guys with this problem have your Rokus powered via the USB port on your TVs?
The power provided by many USB ports goes on and off with the TV. This means the Roku must boot up every time you turn the TV on. If the TV starts up faster than the Roku does and checks the HDMI port before the Roku has finished its startup, the initial HDMI information exchange between the Roku and TV will fail and the TV will report there is no signal.
Forcing the Roku to restart by uplugging/plugging forces a new HDMI "handshake" between the Roku and TV.
See if just switching the TV to a different input and back eliminates the need to unplug/plug the Roku. This should force a new HDMI handshake without having to wait for the Roku to restart.
The problem should go away entirely if you power the Roku using the USB power adapter that came with it plugged into your house power instead of plugging it into the TV's USB port. The Roku stays powered up and doesn't need to reboot when you turn on the tv. If you do that, get in the habit of returning the Roku to its home page when done viewing so that it won't continue to stream and use bandwidth when the tv is off.
Roku Community Streaming Expert
I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well.
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