When rendering our broadcast commercials with h264/mpeg4 codec we often get lip sync errors in the final on air broadcast. cannot see any error on our end, but when it goes on the air, it's off.
There is a known bug in Vegas 8 that causes this, sliding the audio on the track is not a consistently successful solution.
Could it be related to the position of the audio tracks on the timeline?
Really stumped on this, and don't have Vegas 9 yet.