In playback the video only loops the first few seconds of the clip

It's been a nightmare trying to deal with the movie maker. I can't see what's going on in my clips. Most of the time when I press play it just loops the first few seconds of the clip and even if you skip through the clip it still just shows the loop. The problem seems to just be getting worse. I've been looking around on the web and I haven't seen anything else about it. Am I the only one who's having this problem? Does anyone have any suggestions on how to resolve it?

Sincerely, 

Frustrated