I'm running Xubuntu 16.04LTS on an old Dell Optiplex GX520 64 bit computer. The video has been dicey in certain areas. It works perfectly in Firefox and Chrome.

Then when playing back .mp4s, they play perfectly in Xine. But only about 90% good in Videos. Only 80% good in VLC. And only about 40% good in Parole.

So I can watch the .mp4s in Xine but I'd like to edit them in OpenShot Video Editor, but in Openshot the video jerks and stutters (almost like a scratched DVD movie, not quite that bad though).

I've added ubuntu-unrestricted-extra and tried a bunch of other things and although the overall situation has improved quite a bit, I still can't get Openshot working properly.

Any suggestions? Thanks.

I was looking at one particular .mp4 in Openshot and it was pretty bad. I thought it would be indicative of all other .mp4s but when I tried other .mp4s they played much better. It's not perfect but I think I can edit effectively now. Many thanks for all the help!