I'm trying to make a mp4 video that already has english and japanese with subtitles, but when I convert it using mpeg, the video only has english and no subs. on the mpeg main screen it shows the two audio tracks, and if i try to convert to avi rather than mp4 there are multiple audio channels in the conversion box, but the final video always has one audio channel and no subs. is there a way to retain the dual audio and subs?