Hello,
My A10S have problems with video playback. This is expressed in choppy (stuttering, jitter) playback and can easily be seen in panoramic scenes. In other words it's not smooth. This applies to the Samsung videoplayer and others. In most cases I watch not heavy video files (480-720p h264 ~2 mbit/s), so even my old smartphone playing it with no problems.
The first thing I did was clear the cache partition then factory reset. Also I tryed to disable battery optimization, nothing helps.
