Settings > System> About -- what Roku version is shown?
Roku 10.5 is currently rolling out and it reportedly contains some new options under Settings > System > Power on some models. See if any options there fix your problem.
(Unfortunately, at this point the two Roku's on which I have received 10.5 did not receive the Power update, so I don't know exactly what you should be looking for.)
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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