Q. When my video files are combined, the sound is out of sync... why?A. If your video is encoded with a very low quality sound (like 8000hz or below), it is not compatible with MP3 codecs and will be off. If you can locally save the files and comvert them to an avi using at least a 16,000hz sound rate, then re-upload and convert, they should be fine. Your best bet is to save the source files with a higher quality sound in the first place.