I just purchased a Roku Streaming Stick 4k+ and am having intermittent issues with the video not providing a signal. I'm using it connected to my LG 4K TV and after going to sleep for awhile the roku will not wake to show video. I'm forced to unplug the Roku from my tv and power source and replug it in. The Roku is connected to the official USB to power adapter and is not powered from TV. In this state the ROKU responds to my remote presses with a white light flashing when a button is pressed. Clearly there is something wrong with the output of the Roku to the TV. I'm incredibly frustrated and would like to know what my options are.
See if "power saving" is enable (or available) under Settings->System->Power and if so disable it. Pressing a (non-TV control) button on the remote should wake the stick, but the power saving feature seems to be incompatible with some TVs.
I disabled power saving and will try again to reproduce