I have a presentation with 4 heavy videos(56 Mb each). This results in jerky videos. I have tried to storage them in local storage with the same results: jerky videos. Display is an ubuntu 14.04. Webm makes a very bad quality. Any suggestion, please?
Can you redo the videos so that they are the same size of the Placeholder? For instance, if the Placeholder is 900 x 600, but the video is 1920x1080, then the Display is doing extra work having to scale the video to fit the are its being played in.
Can you also check the System Monitor when playing the Presentation and look to see what the memory and CPU are doing? If they are being maxed out, then the Presentation is too much for that particular computer to handle.
Sounds like you may need a stronger CPU. You can also check to see if there is anything else running on the Display (Malware monitor, Antivirus, etc), that may be chewing up CPU. If you shut down those other processes, that may help the Presentation considerably.