iMovie exporting - audio cuts off
Hi guys
I've got an mp4 file that I'm trying to split the audio and video of using iMovie. I've split the audio and video tracks, and deleted the video, but when I export the file as an mp3 (other formats have failed too) the audio only plays back up to a point, after which the rest of the file is silent. I can hear all the audio in iMovie, but not in the exported audio file.
MacBook Pro 15″, macOS 10.15