How to fix/ameliorate jittery 2D animations, that are created using the sprite editor?

I am having a small problem with the 2D animations I create using the sprite editor. I have properly imported my sprite sheet, and have used the sprite editor to slice them. For the most part, the animations runs as intended. However, at run-time the animations appear to jitter, up, down, left and right sporadically. Most of my animations either slightly or severely jitter. One of my theories is that the problem is caused by the sprites not having the same dimensions when sliced. Because the sprite sheets I have aren't formatted to give an equal distant between sprites, I used the automatic slice tool. This sliced the sprites into varying dimensions from 40 X 60, to 48 X 78, etc. Since, it warns that using the automatic slice tool can cause inaccuracies, I believe this might be the problem. However, I don't know if it is. If, this is the problem, how could I fix? If, it isn't, then what could be causing the sprites to jitter, and how do could I resolve it? The object's transform and size don't change, although the sprite renderer shows a jittering image at run-time.Here is how an example of the sliced sprites: