I got a Nova today (having tried a Xiaomi Mi TV Stick 4k a few days ago but returned it due to certain issues). Well I'm getting the exact same issues again with the Nova. Tried lots of different options and tests, but let me try and summarise and see if anybody else experienced similar and maybe found a solution:
Playing through TiviMate (or opening in external players like VLC or Nova Video Player) or using Televizo, for any channels that are FHD 50fps (or 60fps), the video stutters constantly while playing. Play a FHD channel at 25fps (or 30fps), it's smooth and no issues. Even UHD channels at 50fps play fine.
In fact, through Televizo you can see the stream info about the current channel, and the fps varies while playing between 35 and 45fps or so, never reaching 50fps, so I suppose that explains the stuttering. For 25fps channels, stream info displays steady 25fps.
The thing about the Nova and Mi Stick 4k is that they are newer devices from this year. I also tried the older Mi Box S device using TiviMate app, playing the same FHD channels, and they played smoothly, but showed only 25fps (instead of 50fps). Also tried the native Android TV on a Hisense TV, also with TiviMate, same FHD channels tested, and smooth playback but at 25 fps. Both Mi Box S and Hisense had no issues playing UHD channels at 50fps, go figure.
I did come across some info while searching for a solution that seems to indicate that the exo player framework that certain players (like TiviMate) are built on has some bug when it comes to playing FHD at 50fps. But given that I get the same issues when opening from TiviMate in external players like VLC and Nova Video Player, I really don't know.
Anyone with similar experiences or suggestions?