I have several DVD's authored with TMPGEnc DVD Author. I just discovered that when jumping to a chapter from the menu sometimes the audio is out of sync when the chapter starts. But if I jump to the chapter, then hit the reverse button and back it up a few seconds the audio remains in sync even when it gets to the point where it was out of sync a second ago. Sometimes it happens when playing the video and jumping ahead, and if I back up the video a few seconds it gets everything back in sync again.

Any ideas on what might cause this or how to fix it?