I'm running into a problem with Sony Vegas that I haven't encountered in years. The last time was when I worked with a consumer editing software in 2002. The fix was to switch to a professional editing software.
The problem is that with long form videos, the video and audio start off in sync, then drift out of sync as the video goes on. The final file is 1:23:47 (1 hour, 23 minutes, 47 seconds). The "sync drift" is noticeable at 27:57. It drifts farther and farther out of sync the longer the video plays. My best estimation is that it ends up being close to 1 sec and a few frames out of sync towards the end, which is significant.
Here is the troubleshooting that I've done thus far:
-Played on different computers (both PCs) and from YouTube
-Played on different media players. Windows Media Player was in sync, others were out of sync.
-Exported 4 minutes later in the timeline at around 1:10:00 to see if it was in sync. It was. So it is lined up properly in the timeline and the problem is with longer renders rather than shorter.
Any help or thoughts would be appreciated!
Original footage capture:
1st three video clips format
Audio - 48K, Dolby AC-3, Stereo
Export Settings for final:
23.976 fps - AVC
Audio - Sample Rate 48K, Bit rate 128K, AAC, Stereo