MP3 (which is really MPEG 1 or MPEG2 layer 3) is an audio only file, MPEG2 is a video + Audio file. The Web-If extract audio, extacts an audio only file, so I'm not sure why you are calling it an MPEG2 file, I guess it is not the kind of MP3 you was expecting, there are many different sample / bit rates maybe that is what you are getting at