Also, it's possible to disable that home screen ad, if you mess around in the secret settings screen.

Hit Home 5 times. Hit Up, Right, Down, Left, Up. You're now on a secret settings screen. I don't know what its purpose is, internal development? Channel development? Set Image Service to "Dev" Set Home Screen Ad Banner URL to "Demo2" Do a Reset/Refresh of cached settings. Go to main Settings/System and reboot for good measure.

When you get back to the Roku home screen you shouldn't see changing ads anymore, just a static black and white Apple AirPlay image.