DVDLab is not a magical audio sync tool, it is a DVD authoring tool, that just happens to have an option to adjust audio delay in relation to video.
You can do this in many programs, virtualdub/mod, Goldwave, Audacity, Soundforge, to name a few.
My problem is that when I play the video on my computer from the hard drive it is fine.
What plays on your computer (probably in Windows Media Player), has almost NOTHING to do with what will play on a burned disk, or on a standalone player.
You need to find out what type of audio the file uses, at what frequency, and then transcode it to a DVD spec audio file.
Because the burn doesn't have audio in WMP, I would suspect AC3, for which you have no decoder on your system.
If sync is out the same amount through the file, a simple delay at the beginning of audio will usually fix it.
If it is progressive desync (audio starts out fine, then get's more out of sync through the file), it is usually much more difficult to fix.
For all these problems, there are already guides and hundreds of posts on fixing.
For beginners guide to DVDLab, start here: http://www.videohelp.com/forum/viewtopic.php?t=220092
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