I am experimenting with vhs home movies to dvd. EVerything is going well, but I have a question. I can work with the text effects, wipes, video files OK but what are the two audio lines for? I tried putting an MP3 song in the spot and it played while the movie was playing. Question though; Is it possible to lower the volume on the MP3 track so that it is background music and not drownnig out the movie audio?