I am running Ubuntu 18.04 on a computer with an AMD processor and Radeon R7 graphics.
Totem plays videos (especially mp4's) in a very haulting manner as if it hits snags. The audio is fine, but the video is maddening. I've tried everything I know of to remedy this to no avail. I've tried uninstalling codecs in case it might be a conflict of codecs. I installed the Oibaf driver. Nothing works.
This does not happen with other video players. The playback is much smoother.
Any ideas what could be causing this and how to fix it? I would greatly appreciate any advice.
Have you tried
glxinfo | grep Accelerated. There are some others (including me) who seem to have lost hardware acceleration with 18.04. That might cause choppy video feedback.