This was an issue when Voukoder was first launched. A similar issue can be found when using Handbrake for transcoding since they both use FFmpeg libraries. Having said that, I thought the problem had been fixed in later builds.
Because of this issue and differences in formats, I have included an option in most HOS rendering tools to adjust audio offset as shown in this example.
I decided to check the files in DaVinci Resolve as well. And here is the real surprise (look @ attachment) 1. You can't see it in the picture, but both paths are synchronized perfectly. 2. But the first 20 seconds of audio from the Voukoder file are "missing"! a) but only the graph is missing - the sound is actually playing! b) but it isn't played from the beginning - less than the first second is missing (it is exactly played from frame 58 - from the red line in the picture) (Summarizing: frames 0-57 - no graph and no audio, frame 58 to ~20s - only the graph is missing, sound is playing, from 20s - everything is ok)
There may be a problem with the new decoder in Vegas, but it looks like the encoder in Voukoder is just causing some problems for other programs.
As I use Voukoder only for final renders, which play absolutely in-sync on my TV, I really don't care how Vegas or other NLE's interpret those renders when re-imported on their timelines. To my opinion and experience, don't trust blindly how Vegas interprets those re-imports.
Just tested it with some mov/pcm footage and can confirm the bug's still there in ffmpeg4, ffmpeg5, and Voukoder 11.
Also noticed Voukoder 11 lost its Intel/qsv hardware support... even the one that's marked Intel Arc beta. That's an ffmpeg5 bug. Probably going to back-pedal Voukoder on my systems to the one built on the last ffmpeg4, which I think is v4.4.1. UPDATE!!!: There's a trick to making qsv available in Voukoder... gotta go into Windows, Graphics, Advanced and set Vegas to use an Intel igpu or Arc board... then the Vegas plugin sees it and menu items appear. Similar trick works for ffmpeg v5 decoding... just point ffmpeg to an Intel gpu in Windows and use "-hwaccel auto".