I have a 620 x 348 f4v that has a one pixel vertical line on the left and a one pixel line on the right. When this video is played with an instance of flash.media.Video the left line takes up 2 pixels instead of 1 and the line at the right is not visible. When the same f4v is played with an external flv player it shows both lines as expected. Likewise when I tried using a FLVPlayback component.
I have tried creating a new flv with just a left and right line in it and the same behaviour resulted.
I have checked in my actionscript and the video object is the same size as the f4v and is not resized (other than making it 620 x 348).