iMovie export audio out of sync
Hello,
I've been editing a 1hr video using iMovie. It uses video from two different cameras (one gives .MP4, video files, the other gives .MOV), and audio mostly from a separate recording device (.WAV). I've been lining up the audio to the video manually between edited shots, and it looks like everything is in sync within the iMovie preview playback.
However, when I export it to .mov, under better quality compression, 720p (as this gives 26GB file), I noticed some of the shots are slightly out of sync with the audio, and only in the exported file.
On the 'Get Info' for each type of file, both the .MP4 and the .MOV files say:
Dimensions: 1920 x 1080
Codecs: Linear PCM, H.264
Audio channels: Stereo
Except the .MOV file additionally says 'Timecode' within the Codecs section, and has an additional section saying 'Colour profile: HD (1-1-1)'
The audio recording info says:
Audio channels: Stereo
Sample rate: 44.1kHz
Bits per sample: 16
I've read elsewhere that the difference between 44.1kHz in the audio and 48kHz from the video could cause this problem, but the strange thing is that I'm only seeing this happen with some clips and not others (mostly with the .MP4 clips, and maybe a tiny number of the .MOV clips out of several). The audio has been trimmed here and there in iMovie to cut out small parts, but always lined up manually as close as possible to the video, and as I mentioned there is no noticeable lag anywhere in the iMovie preview, but it only becomes apparent in the exported .MOV file.
Can I ask how should I go about resolving this?
Thanks in advance!
MacBook Pro (2020 and later)