There probably isn't a fix. Sometimes Roku devices, like pretty much any computer, need to be rebooted. You can try getting rid of apps you don't need, but I don't know if that will help. Another thing that may or may not make a difference is "Fast TV start" under Settings->System->Power. Try it both ways. Finally, do you really have to unplug the power? A "System restart" under Settings->System->Power should do the same thing.
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