I have some problems and questions about simple de-multiplexing. Some of my videos had problems de-multiplexing. I got to the Simple De-multiplex tab, and enter the Input file name, when I enter that into the field for input, the audio output is filled in but the video output appeared empty. After that I tried entering manually in the video output field and I get the message: "Illegal MPEG Video Stream". However, for some of the other videos, it work perfectly fine. Does anyone know the reason behind this? Please help me is anyone know why this is happening. Thanks in advance.