need help with audio/video out of sync within a clip in iMovie

Select the video clip and do a Modify/Detach Audio. Use the slider located to the right of your screen above the timeline to expand out your timeline. Then Control-click on the detached audio clip and select Show Speed Editor from the drop down menu. That will reveal a speed slider handle in the upper right corner of your audio clip. Slide it slightly to the left to slow the audio, and to the right to speed it up. Work with it until you get a good sync. You can do the same procedure with the video clip if you prefer, in which case you would want to move the speed adjustment slider to the left to slightly speed up the video to sync with the audio. .

-- Rich

😊. Thank you for the kind sentiments. Glad you got it working for you.

— Rich