I have the same issue and people kept trying to tell me it was my issue not ROKU or Netflix eventhough I kept telling them everything was fine until the last firmware update and nothing had changed on my side. So I stopped trying to get help on here. Glad to see I am not crazy. I did a factory reset and that helped a bit. Also, I noticed if I start a video, then stop it and back out, then go right back in, it helps the issues of you guys are talking about and stops it defaulting to a low quality.
ALSO, since the firmware update, Fox News podcasts just keep looping and looping. I checked their format and it is mp4 just like cnn and msnbc, but only fox podcast is affected. I thought ROKU said there was going to be a fix very soon but I have not seen anything posted recently. I am having to use my Sony Blu-ray player to watch these which is a pain. I also tried streaming the podcasts through Chaneru thinking it would work with the locally downloaded file in my itunes, but it loops as well. So, there is something squirrelly in the firmware. I get tired of watching cnn, msnbc, and then having to turn on my blu-ray to watch fox.
Well, guess what. I just loaded Chaneru's new 1.4 beta, and although the video starts with a glitch of one loop cycle, I can stream the foxnews podcasts that are stored locally on my computer although sometimes video and sound are out of sync. But this at least makes it viewable now. But still think there is something off in the firmware update. THANK YOU CHANERU! Love your channel.