Okay I have some mpegs extracted from vcds that have dual audio, cantonese and mandarin, and I want to place it back into the mpeg with just cantonese and have it in both left and right channels. Both audios are perfectly in synch with the video. I have tried demuxing the audio, sticking it into GoldWave, deleting the mandarin channel and copying over the cantonese channel to the empty channel, and saving it. However, the file will always end up slighty longer than the actual video (a few seconds or so) and when I go back to multiplex it (I've tried using both mpeg-vcr and tmpgenc), the audio will always be ahead of the video and out of synch. I am not sure how consistent the displacement is but it always happens. I have also tried using the mpeg video wizard by womble and just checking the option to duplicate the left. This creates the same affect, albeit all within one program and much more efficiently, but the audio is still out of synch in the same way.

Although I can probably delay the audio to offset the synching, I do not know if it is consistent or not and I have quite a number of vcds to work with. Is there a way to keep this problem from occurring at all?