I thought this was just my iPhone wreaking havoc, but I'm starting to notice audio creep on a lot of things.
It's always a matter of degrees… my original iPhone audio is *slightly* behind usually due to bluetooth EarPods, etc, but just by milliseconds so not really noticeable, and honestly a-ok for what I need it to be. But then after import/edit/export in FCPX it seems to be off by a tiny bit more. Then, especially IF the file is large (1080p, 4k, etc) then uploading to YouTube, Instagram, Facebook, etc, results in drastically drifted audio. I've found myself having to go back in, RE DO the audio, and even sometimes "cheating it" in the other direction to make up for the drift.
This happened recently on a non-iPhone shoot, too, with a Nikon at 30FPS 1080p, and audio recorded on a Zoom H6. I let FCPX auto-sync the audio, and it was fine. UNTIL I exported, and uploaded.
This seems to happen no matter how I export; eg., Master File vs Prepare for Facebook.
Any idea what's going on here?
I've searched the webs, and seems the only solution anyone has is to re-encode the audio in handbrake or FFMPEGX, etc.
That said, there IS a correlation between the size/quality of my output and the amount of audio drift. Which is weird, probably has to do w/ the backend/upload in each platform.
Also weird: On my Nikon I shot 29.97, and when I sync w/ the wav audio the resulting clip went down to 23.98. Not sure how that happened. Since I'll be doing more sync in the future I'll need to figure out how that happened.
Dumb question: since my Nikon "30" is really shooting 29.97, I'm assuming I should stop choosing 30 for my projects?
Thanks… I feel like an idiot. Hopefully my stupidity helps others!