Audio out of sync AFTER importing

while this may solve the issue, i think your process is extremely time consuming.  as another person in this thread has alluded to, all i needed to do was to change the speed of the audio track in the timeline, in my case to 99.97% for a 15 minute clip and the whole thing is in perfect sync.  jury is still out on what the export of this will look like but in case it is different from what i see in my timeline now, i will post again.  thanks - good luck!

The whole problem of video and audio being out of sync... After spending hours with it I finally found the reason. The data in the MPEG header produced by mobile devices (at least my iPhone) is slightly off. The MOV-file declares having 30 fps where in reality it has only 29.983 (some tools show the correct value - VLC in the "Codec" menu, HandBrake in the log file - there seem to be two values in the header, one being incorrect). Premiere thus misinterpretes the lenght of video. Audio has its own length. The common sample rates are 44100 and 48000 samples per second. So the length of audio is count of samples devided by sample rate.

Premiere does have the appropriate function to assume another frame rate (right click the media clip in the project media) but it does not solve the problem in a straightforward manner. While scaling the video correctly, it also scales the audio, desync remains. In order to solve the problem with Premiere alone you have to do the following:

1. import the media clip twice
2. for the first instance change the assumed sample rate to 29.983, for the second instance leave it untouched
3. insert the first clip into track 1, the second into track 2
4. from track 1 delete audio
5. from track 2 delete video
6. drag the remaining audio from track 2 to 1

Play. You will notice that now audio an video are finally in sync. However, video and audio remain detached. A better solution is to correct the frame rate externaly. The good news ist that just setting the correct frame rate does not require the re-coding of the file. The bad news is that I did not find a tool to do it easily. Quicktime is a rather complex format...

Would you like to know why it plays fine in players and not an editor like Premiere?

VFR= Variable Frame Rate.

Premiere expects you to deal with frames that were dropped or weren't recorded by either turning ON the auto function, or retiming the audio yourself to compensate for the frames that aren't there.

"How can they not be there!?"

It's really very simple.  Most cameras do image stabilization at least one of two ways--the first is inoccuous, using floating optics to maintain stability--and the second method, which has become extremely popular, is to detect motion of the camera, or the outer edge of the frame of video and then drop some of those frames to avoid excessive frame changes that will degrade the fidelity of the following frames when uncompressed.  This dropping of frames PLAYS BACK fine, as most apps support "REFRAMING".  Look in vlc at the full info on the stream of video, and find the section with the name "REFRAMES".  If this shows up, you're missing frames, and the app replaces them by blending those around them intelligently into a new "Intermediate" frame that keeps visual continuity.  Premiere is more of an ALL AROUND kind of app.  It offers the amenities of automation, but you have to turn them on.  In PREMIERE, find your source clip in your project panel, right click, find FRAME BLENDING and turn it on.  When you output your video, check the box at the bottom that says USE FRAME BLENDING, to make sure it continues the action in the output (HINT: This option is also in Adobe Media Encoder, which ships with Premiere Pro, so you can queue your export).  By turning on frame blending, you are telling Premiere to blend any missing frames the same way VLC would.  The difference?  It won't do it automatically, which some people prefer.  In some cases, with high-definition video, you get horrible pixellation or there are so many missing frames that the blend horribly blurs some motion areas.  In these cases, It's usually best to either blend it yourself, and make slight adjustments in After Effects or Photoshop, or to retime your audio so it is back in sync.  See below for most common methods in film and professional video.

RECAP: to turn on auto fix, right click the file in your PROJECT PANEL, Select Frame BLENDING to turn it on, then drop in any sequence.  It will try to play it back, but it may need to render a preview first.  Good luck.

For the Curious and Intrepid...

Pro Tricks:

The most common method in the pros is to retime audio using a few key settings.

If you can record at 24 Frames per second (a full 24 frames, not 23.93, you can use an old audio trick to retime what you need to with excessive camera shake or frame drop.  Set your audio sampling to 48k or 96k, nothing below 48k.  Bit depth 16-24bit is great fidelity, and 16bit is cd bit depth.  48k is FILM audio standard, just as 24P (24 progressive frames per second) is the video standard.  With 24 frames in a second, you have 48000 audio samples in that same second, and for each frame, you should have 2000 audio samples.  In audition, or premiere, you can clip audio by Frames.  This means you can find an area where things drift, find the spot where they drift (use Program monitor with FRAME MONITOR on--it lets you know where there are dropped frames from gfx low power or from missing frames in video, though both look the same).  You'll have to use the mouse to move across the section a bit slowly.  Then, where you see the missing frame, cut the audio in the frame after it, leaving the video alone.  With several missing frames in a row, this takes a while, and your audio might get a little hinky.  So you can fade it out quickly on the frame before, and back in on the frame after the drop.  You'll also have to clip the video into subclips and replace it in your timeline.  When you export the video, turn off Frame Blending, and you should have sync'd output the professional way.

If you use 23.93FPS, this will not work.  Use a NON-DROP-FRAME setting on your camera, or record your screen with full 24 frames Progressive video.  It will remove exactly 2000 samples of audio every frame you clip.  Otherwise, it will vary by which frame you're in, and won't line up the same.  You might clip too many or not enough samples by only a small ammount and have to either undo the clip, or clip even more.  If this does happen, you may have to go down to the SAMPLE level and view the entirety in audio samples, using very short, very slow selections.  This isn't just tedious, it's like using a jackhammer to drive Rail Nails through your head.  But it is the PRO way.  This is the methodology that Premiere was built upon.

I normally don't post on boards, but I've had a similar issue to the rest of you and I just found a solution. Here is my quick description and solution.

My client shoots all their videos using apps like Periscope, Snapchat etc.  And if you import of any of these videos from an app that are .mp4 they will go out of sync past 5 mins. Someone stated this, and it is correct.  Because the iPhone keeps resetting to shoot in the best environment, it changes every start and stop. I'm assuming the phones uses VBR to save on resources.  I tried Handbrake and it doesn't work on a Snapchat video, because the video has too man breaks. It's literally like a bunch of many videos stitched together. So you know the VBR is going crazy.  

I edit on a mac and converting the mp4 using Quicktime pro didn't work either.  My friend that edits using Final Cut Pro didn't have an issue using the videos I converted using QT pro, but when i put the .mov into Premiere of course the sync issue was still there.   Someone mention making the VBR video into CBR. That sounds great in theory but when the #1 go to solution, Handbrake, doesn't work then what do you do?!  I use to use FCP religiously until Apple made it into iMovie Pro.  When I used FCP, I used it always with Compressor because I was the batch video king. So that's what I finally did here. I took the SnapChat video and encoded it with Compressor using a custom QuickTime export setting (H.264, 720p, data rate: 10,000kbps, and 29.97fps). When I imported the SnapChat video it worked. No sync issue!  I told that long story to cover most of the stuff that was stated above, because it didn't work for me.

Summary of my solution:

Re-encoded your video with Compressor using a custom QuickTime export setting (H.264, 720p, data rate: 10,000kbps, and 29.97fps)

Yes, it does suck to have to use another tool to accomplish a task. And yes it is an Apple made product. But so is the iPhone, so it kind of makes since. And it beats me buying FCP. 

If there are typos in this reply, forgive me. I have to get back to work now. LOL.

Which gopro ann?  I've had footage from several.  OIS is a stabilizer that will do a VFR in extreme conditions, EIS will pretty much do VFR no matter what.  I've had both types of footage, and I'd say OIS from the gopro.  I've checked the framecounts and compared after a pass through AME with frameblending.  There are several REFRAMES done to match CFR.  And the ending timecode changes to match the reframes.  Be careful.  You can turn off the stabilizers, but with them on, you risk VFR.  Saying that something doesn't do it out of the box may be right, but some people turn it on without knowing it, thinking it will help.  In the 120fps modes, I've seen VFR.  It drops to 110 or 113 at times, but in normal modes, much less.  Please give the model number and modes.  THat really helps a lot more.  I'd like to know which one.  I'm thinking of picking a few up if that's the case.

For audio sync issues, you're almost always relegated to one of two options:

Handbrake

AME with Frameblending turned on

However, you can also turn on Frameblending in PrPro.  Right click on the clip in the project browser, and tick frame blending before placing it in the timeline, or right click on it in the timeline, and tick it there.  That should temporarily allow your work to continue.  However, you may get some skipping.  SO... ...When it starts, set a work area, and render with the skips in the center of the work area.  This will "create" the blended frame, and prevent audio artifacts.

This is all for CS6 and higher.

Very helpful tip. Thanks!

We've got the same audio out of sync problem (and even sometimes jumping to the beginning of the Clip) with Premiere Pro CS6. The mp4-Files are recorded in 4k by a Panasonic DMC FZ1000 with konstant Framerate and are played back without any problems in all mediaplayers and can be edited also without problems in Sony Vegas and other NLEs. So it's seems there's not just a problem with variable Framerates but with the mp4-Format in general in PP. Is there hope for a solution? Otherwise we would think about switching to another NLE.

Thanks mate, you saved lot of my frustration.

Hi there

WHAT WORKED FOR ME: Having come across this problem in Premiere CC 15 and reading this thread - I realised that my Quicktime file that I had originally exported was converted with AAC audio (click on the audio tab when exporting to see the format of the audio). I therefore opened Adobe media encoder - converted the .mov file to another .mov but this time making sure the audio setting was changed from AAC to 'Uncompressed'. I then imported that file into Premiere and it played fine with no audio sync issues. Hope that helps someone!

In short if you are going to import an exported file back into Premiere make sure to always set the audio when exporting to Uncompressed!

I'm not a computer geek and I speak plain English, so if this is confusing to anyone I apologize. I work on a Mac mini and absolutely hate workarounds and spending time solving problems created by programming idiots, so here goes...

First off, you don't need any Handbrake bullshit, any other third-party software bullshit, or some programming nerd blowing smoke up your ass. When I plug in my GoPro Hero+ to upload video they go directly into the Photos app -- when of Satan's true evils -- but there you are. Once a clip is there I export it by selecting..."Export > Export Unmodified Original." Create a folder for your export and dump it there. In PremierePro -- Satan's other masterpiece -- go to your Project panel and Import the file you just exported.

That's it.