Having a little issues

Its been quite a long time since I used this, I went back here recently it was running like a charm, its a great video editing app, but there is one slight problem. Ive just started working on a new video, i left the app to take a break and came back then started noticing the clips are longer than they should be, they are longer than when I left them. I dont know if its a glitch or a slight bug but itd be lovely if you could oversee this, maybe its just how it is - though I did last time and it didnt do that.

WillCadeson about iMovie, v2.2.3