Skimmer options in iMovie grayed out

When I go to iMovie and try to use the arrow keys to play audio to make precision cuts, the audio doesn't play when I skim over clips there's no audio. Audio plays fine when you hit the play button or the space bar. I've tried everything. Reinstalling iMovie, throwing away preferences, rebooting the machine, restarting iMovie several times. Nothing seems to work. I'm thinking it is a preferences problem but it's lower level. Has anyone else have this problem and if so, did you solve it? How? I have tried other video editors, none seem to be as intuitive to me as iMovie.