Audio going out of sync over time

[CKFC Podcast]

I have a 3 video files. A zoom recording at 25 FPS 720p and 2 seperately recorded video files from iphones both recorded at 30 FPS 1080p. Because iphones shoot in variable frame rate,  I have used Handbrake to convert the iphone videos to a constant 25 FPS and put them all into a premiere pro timeline then manually synced them up to a point where we clapped at the beginning.

The problem is that over time, the audio becomes out of sync again. Is there any way of making that not happen?

[Joëlle Bh]

Hello,

Could you please post what are the sequence settings that you're using

[CKFC Podcast]

For the sequence, I just dragged one of the 25 FPS constant framerate. clips onto. a new timeline and it created the sequence automatically. I didn't input. anything myself.

I've also tried it with dragging over the Zoom video first. and then the others.

I've had to edit it as best as I can this week, but I film and edit a 1 hour long video podcast every week so I need to really find a way of recording the video and audio at the same speed for the next record.

The videos are recorded via iphones and the audio is recorded via usb microphones through the Zoom video chat client.

Happy to use different software or even purchase something reasonably inexpensive if it is needed but I just need the video and audio to match with as few extra steps as possible...

If you have any tips at all then I would greatly appreciate it. Trevor

[Averdahl · Accepted solution]

...so I need to really find a way of recording the video and audio at the same speed for the next record.

By @CKFC Podcast

That will never happen. Let´s say that you have three cameras from the same manufacturer set to the same settings. All three have an internal clock that will differ a tad from each other. So if camera A gives you 1 hour camera B may give you 1 hour and 6 seconds while camera C may give you 59 minutes and 52 seconds. (Replace camera A with source A) Material from different cameras/sources will drift even more.

You will always have to manually sync cameras/sources over time since all will drift apart over time. Use the audio waveforms in the timeline to locate the sync issues, make sure to un-check Rectified Audio Waveforms to easier to sync waveforms. I tend to cut up the video in 4 or 5 minute segments on the timeline and adjust the sync for each segment and then trim off a couple of frames to adjust for the un-sync and then move them together. It´s easy, it´s tedious but it is possible to do without corrupting the end result.

There is no other way around it.

[CKFC Podcast]

Thank you. I spent hours researching this and this was the first time I've seen anyone word it like this, but it makes. sense now.