Imovie has a persistent problem which prevents me from further editing movies

Anytime I tried to edit movies, there would be an instance where I’d play a project and the sound would stop working then I pause the project then replay, and then the loading mouse would appear and basically I’m stuck and the only way to stop this issue is to force quit Imovie. When I open it again, the same thing happens. Like mentioned before, this always happens when I use Imovie. Is there a way so this software runs without any interruptions?