iMovie turned off audio during trimming

Hello there. Before the last iMovie update, it was really easy to trim the video to the milliseconds because when I shifted the vertical bar on the timeline with my arrow keys (back and forth), I could hear the sound in the video. Now there's no sound, only if I play the clip.

What can I do to return the sound or the previous version of iMovie? Because now it's impossible to edit the clip flawlessly, cutting out the unnecessary stuff precisely.

Thank you.