I have a Roku Express, I'm using it with a Vizio TV and have a 100 Mbps internet connection through Windstream, so plenty of speed. My Roku "glitches" quite often: the screen gets a white horizontal "flash" with short static sound and the audio drops out for a half-second. It can get quite irritating.
This glitch happens no matter what Roku app I'm using: Netflix, Shudder, whatever. For comparison's sake, my Vizio TV also has a built-in Netflix app, but I've checked many times and it never glitches. If I immediately go back and use the Roku Netflix app again, I get the glitches like always. So the problem can't be the internet connection.
Other troubleshooting I've done: I've uninstalled-then-reinstalled the Netflix app. I've unplugged the Roku device. I've done the System Restart through the Settings menu.
I've only been using the Roku Express since October, so six months. Anybody have any idea how to fix this?
Thank you for the suggestion to replace the HDMI cable! I never would have thought that that could be the culprit. My understanding was that an HDMI cable either makes the connection or it doesn't; that you either get full picture and sound or you get nothing at all. However, I replaced the cable and haven't had any issues since.
Sorry it took two weeks to respond. Amazon's moving slowly delivering packages (containing my new HDMI cable) due to the covid-19 virus these days.