Audio Out Of Sync Over Time - After Handbraking

Hi all,

I'm editing a 4 hour long video that has been handbraked to force a constant framerate. The audio seems in sync for about 2 hours then slowly drifts out of sync.

I'm dealing with one video clip which contains the audio. Audio is at 44100 hz.  I also have a video overlay on top with opacity set.. no audio coming from this overlay.

I'm banging my head against the wall trying to figure out why everything is becoming out of sync? I've searched through forums and google fu'd the hell out of the issue but it keeps bringing me to articles saying handbraking will fix it.

Sure, Handbraking works when the audio/video are out of sync right from the get go.. but not with audio/video becoming out of sync over a long period of time.

I rarely work with videos at this length so it seems like that is playing a part in the issue?

I have handbraked the video to force a constant frame rate (CFR) and have confirmed with MediaInfo that the video frame rate is Constant.

I've unlinked the audio and video in the sequence timeline so I could view the properties of each and they each seem to match.

I've included some screenshots so you folks can check out my settings

[Audio Properties when Unlinked](https://abload.de/img/audioproperties_whenuwjqu2.png)

[Video Properties when Unlinked] (https://abload.de/img/videoproperties_whenu3fr1r.png)

[Sequence Settings] (https://abload.de/img/sequencesettingscgpty.png)

[Media Info Settings for File] (https://abload.de/img/mediainfosettings78oyk.png)

All help is appreciated!

Thanks