I have the same problem. I have Sharp roku tv, suddenly turn black screen. I unplugged and press power button for 30 sec, wait for 10 minutes and plugged power back on, but screen is still black. None of the tv remote buttons are working as tv is not responding. power light on tv is blinking sometimes and it stops blinking. This tv is only 3 years old, I don’t think it is end of life yet….. what can I do?
Roku Community users have confirmed that they were able to resolve their similar issue by unplugging their Roku TV for 10-15 minutes then plugging it back in. Have you tried that specific troubleshooting step to see if that helps?
Please keep us posted and we will be able to assist you further.