I’ve had my Roku Premiere (4620 series) for a few years now and never had this issue before. It was working perfectly fine and then all of a sudden just stopped working. I will try to wake the Roku and get the “bouncing” Roku loading screen, then all of a sudden the screen will go black and say there is no signal. I have read TONS of articles online and done all the troubleshooting that I can find on every support page, so to save some hassle (and my sanity) here is what I’ve tried already:
- unplugging all cords from my TV and Roku; taking batteries out of the remotes and replacing them
- trying different HDMI cables; switching HDMI ports on the TV; flipping ends of the HDMI cables
- resetting the Roku (with the button on the back and with the remote since i can’t get into the settings)
- rebooting my wifi (although every other device has no trouble connecting)
all the cords to the Roku are the originals (and it’s the original remote).
I'm not sure if you solved your problem but my premiere stopped working out of nowhere and wouldn't connect to my wifi after connecting with no problem for months. I tried everything. We had recently switched to Spectrum so I called them and they did something on their end that they say made my device "more discoverable" and boosted it somehow. It worked. Not sure what they did but it was the only thing that helped.
Is there a light on the Roku device once the screen goes black? How are you powering the Roku device? Is the device plugged into the TV USB port or is it plugged into a wall outlet? Have you tried performing a factory reset on the Roku device to see if you are able to resolve the issue?
Please keep us posted what you find out. With more information we will be able to assist you further.