Under "Settings > System > Advanced system Settings > Advanced display settings" some Roku devices have an "Auto-adjust display refresh rate" item.
If this is enabled, the Roku circuitry sends the signal output at the refresh rate (frame rate) used by the original source material, commonly 24 fps (frames per second), 25 fps, 30 fps, 50 fps, or 60 fps. Every time the source frame rate changes, the TV must adjust its display to accommodate the new frame rate, which on many sets results in a short blackout.
This can happen when starting/stopping new programs, and when going in/out of commercial breaks that have a different native frame rate than the programs they are inserted into.
If "Auto-adjust display refresh rate" is set OFF, a frame rate of 60 fps is used for everything and the TV doesn't have to adjust on the fly.
The tradeoff here is that movement of things on the screen for non-60 fps sources may not be as smooth with no frame rate adjustment. You have to decide whether this change is worth it to you.
thanks for the response but this is happening mid program - if it was only during breaks for ads or changing programs, I would be less concerned. Screen goes blank, sound keeps on playing. Classic HDMI handshake symptom. And like I said... unplugging the roku so I can power things up in order seems to resolve it. I'll see if by chance my Onkyo has a powered AC outlet - and if so, that might resolve it.
