Audio out of sync on MP4 file. Fixable?

[liverkick]

I recently converted a bunch of mkv files to mp4 using GOTsent, handy little tool that. Unfortunately one of the files has about a second delay between the video and audio. I already dumped the mkv files so I'm not sure if it was due to GOTsent error or the source file was simply faulty, but regardless I have no idea how I could go about fixing the resulting mp4. Would appreciate any help, thanks!

[rumplestiltskin]

I was going to suggest QTSync but I see you're using a PC and it's currently only available for OSX.

Others care to chime in?

[Krispy Kritter]

Check the original file for errors. You may be able to correct the original file and perform the conversion again.

Otherwise (assumming the audio sync is a continuous offset from start to finish), you will need to demux the audio, add/remove audio from the beginning of the stream, and then remux.