How about creating a control surface button that triggers all the elements.
Selecting the preload option for the media bin might help.
Also wonder if driving everything from external time code might be the solution.
If you are trying to scrub through h.264 (or some other mp4 type media) you are probably going to have a bad time. In this case I’d suggest converting your media to HAP or PhotoJPEG.
(beyond that, if you are having weird glitches or delays, please send us a bug report from the Help menu!)