Same issue.  Screen just blinks for a second or two.  Sometimes it happens all night long -- sometimes never.  My Roku is connected to Ethernet (it happened on WiFi too).  And then it RoKu goes into a Samsung tv with an HDMI cable.  I noticed a lot of people PM'd the Roku moderator.  Is a fix available?  What is the outcome of all of the PMs?

Given the details you provided, this is most likely an issue with the HDMI cable, the seating of the cable, or may relate to a specific channel or content that you are watching. 

I would recommend replacing the HDMI cable connecting your device to your TV, ensuring that you are using a HDCP 2.2 certified, high-speed HDMI cable, being cautious not to bend the cable or damage the connectors, and try plugging the device into a different HDMI port on your TV. 

If you still observe the issue occurring from there, please take note of exactly which streaming service/channel you were watching, along the specific content title (movie/tv show). After you see the issue on screen, generate an issue report tracker ID by pressing the Home button 5 times quickly, followed by the back button 5 times quickly. Please send me a PM with the details above, along with your Roku account email address, and the Roku device serial number from Settings>System>About once more. 

I'll help take a closer look and share your report with our team for further investigation. 


Thanks,
Tanner

I’m having similar symptoms. I have a Roku Uktra bought last Christmas but never used until a couple of weeks ago. It’s connected to a brand new Vizio P-series Quantum X. Every few minutes the audio and video cut out for about a second. This happens in the Roku menu, or while watching Netflix or listening to Spotify. Tried different 4K settings (30/60 hz, HDR/non-HDR) but it didn’t make a difference. Tried two different 4K rated HDMI cables, and different HDMI inputs on the Vizio. The only way I’ve been able to avoid the flickering was by setting the Roku to 1080p.

Addendum: I found the HDR subsampling menu under System > Advanced system settings > Advanced display settings and changed it from 4:2:0 to 4:2:2. Set the display mode back to 4K UHD 60Hz and so far it's been flicker free.

I’ve plugged my Roku Streaming Stick+ Into a HDMI port (Sat/Cable) on my Pioneer VSX-524 receiver. The screen will go black (sound remains), stays black for a moment, and then goes to static and the picture returns. Sometimes the screen goes black and stays that way. If I pull the stick out and reinsert it the picture comes back.