I turned my tv and Roku express on this morning and the screen is flickering in and out constantly. I changed all HDMI cords. Unhooked the Roku from our stereo system and hooked it directly to the tv HDMI. Changed out the Roku from my bedroom and it is still flickering. My PS4 works fine, with no on-screen flickering. I looked it up online and found this.. In Settings>System>Advanced system settings>Advanced display settings, go to 'Auto-adjust display refresh rate' and make sure this is 'Disabled'. My Roku does not have Auto-adjust display refresh rate. What can I do to fix this. I has worked fine for a couple of years.