Here's a problem I've only experienced recently with the roku application, the version you can search for officially and install directly through the roku itself. Now it doesn't _always_ happen, sometimes it does at the beginning of some videos, sometimes partially into a video this happens. Sometimes it clears up itself and the video is watchable again, sometimes it isn't and I'm forced to exit the video and resume where it left off to continue seeing clear video.
I know others experience this issue, and I even was able to capture a video of it playing a video goofy.
I've attached the ffmpeg logs, but the video and server logs are too large hence shown below as links.
video demonstrating goofy video playback, taken with my 2k13 n7, it's a bit big at 79MB:
roku client version 1.16.7
mediabrowser server version 3.0.5112.40848
note: Anyone experience the same issue or the cause? O_o?