I'm streaming to my Roku 3 connected to my TV on the top floor using a Plex server I'm running on my Mac. I recently started seeing the following issue with every video file I try:
I have a two-channel, h.264, mp4 file. It seems great when I play it with VLC. When I play it on my Mac's Plex media player, it appears OK. I hurry upstairs and play it on my Roku, but after a few minutes the video starts to flicker and become distorted as if there is a poor wifi connection. The video is initially terrible for around three seconds before improving. A minute or so later, it malfunctions once more. The video now plays glitchily, just like it did on the Roku, when I return to the computer and play the file. After streaming to the Roku, I tried it on both VLC and Plex media players, and the same picture problems appeared.