What model of roku is this and which firmware version?
The roku is very trusting of the mkv header, even when it is obviously wrong. If you remux it with MKVToolNix copying all streams, does it still have this issue?
With the roku, it makes everything into 60fps. The only time it won't is if you enable refresh rate switching. Then it will attempt to match the refresh rate, but on most TV sets, this produces a noticeable effect. The TV may go black for a few seconds as it switches. This is normal, but might be undesireable.
If the MKVToolNix remux doesn't fix the issue, can you enable refresh rate switching and see if that works? If neither works, remux or refresh rate switch, this is likely a firmware issue. Something to ping roku with, perhaps.
If this is a roku3 or earlier, I apologize. You cannot use this feature it requires mstar chipsets with quad core mali450, not the older arm chipsets with dual core mali400. And if you do have a roku3 or lesser, word on the street is roku OS9 isn't written for roku3 and less. So these models will likely not get OS9 at all. Stay tuned to your favorite newsfeed to see what information is known about roku OS9. New roku models on the way for Q4 too..no fcc-id to report yet, they haven't filed yet. But since their IPO makes them a public company, their latest SEC documents speak of new hardware. Whether this is just new rokuTV models, or new roku models is anyones guess.
Above is the easiest way to peruse their fcc filings. But nothing new..
Edited by speechles, 21 September 2018 - 03:26 PM.