Short videos not playing

We have a video presentation that uses approximately 3 seconds of video. When we were using a 30 second clip, it would work, however, with the 3 second clip the video begins to play but does not finish.

The computer is a bit older and uses a 60Hz refresh rate, which we thought might have something to do with it, but I couldn't find any definitive information about refresh rates.

The program with the shortened video works fine on another computer, so we don't believe there to be a problem with the program itself.

Any help would be greatly appreciated!