Trimming audio in imovie

At the risk of sounding like an absolute fool, i can't trim the music-audio of a video i am working on in imovie. I exported it from the jingle file, and dragged it to my timeline. So far so good. I can drag the audio file as a whole, but i can't trim or split the audio. After spending 3 hours checking every menu and submenu available i just have to conclude that i cant find the answer by myself. Please help me out!