Same problem on RPi 2.
Only tried using MMAL. Can confirm that the audio stream plays fine, but the video stream gets worse the longer it is played for. By this I mean that the first 10 seconds of playback appear normal, but then for every second of playback after more and more frames are dropped.
|Playback time (s)
||Actual Framerate (fps)
The above figures are by no means scientifically accurate, but definitely getting <1 fps after less than 1 minute of viewing. Pausing and resuming playback seems to reset the playback time listed above to 0, but it quickly degrades.
Downgraded to 9.2.1 and everything working well again.