I have always used Ulead media studio video editor for video editing. It works nice for me. But your problem does not seem to be one of the video editor's. The audio is not properly synchronised probably because of the difference in frame rate and kbps you are compressing the movie in. Try to complress in the original frame rate of the movie. Also play around little bit to strike a balance between compression and quality. Another thing to try is use DIVX codec instead of normal mpeg. Divx gives a much better quality for a small file size.
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