Low video quality on all movies and tv shows

I'm not sure if this is a known issue or I'm doing something right, but every video I try to play via the PS4 app is pixelated. I used RasPlex (Plex for Rasberry Pi) for a long time and I had no problem streaming full hd movies on it with perfect quality. The only problem was that some codecs were not supported and I had to switch to my chromecast to watch them. I subsccribed to Plex Pass just to be able to use PS4 app, but the picture quality is incomparable to RasPlex. Is there anything I can change to improve the video quality?

I was about to make the exactly comment.

I have the 2nd Generation GoogleTV. Although the UI on PlayStation is nicer, the quality of the streaming media in GoogleTv is way better than on PlayStation. I can't watch anything on PlayStation in that way.

Same here, about a week ago, any video I play it's always pixelated.

Can anyone help with this issue?