Should be more along the lines ofAVISource("C:\Documents and Settings\M*****\My Documents\My Videos\video.avi", audio=false)
BicubicResize(960, 720, 0, 0.5) # Bicubic (Neutral)
AddBorders(160, 0, 160, 0, 0)
ConvertToYV12()
Regardless, I'm thinking that the de-synchronization of the audio video is of a different nature. Though, you should probably change the script first and see what happens to the resulting video.