Control the audio channel / track by using directshow ??

[parker]

hi,
i have write(using vb.net) a small karaoke system which can play .mpeg, .AVI, .VOB 1 format video file by using vlc. but currently i'm facing a problem which i cant control the audio channel / track in the music video. Is that any methods or ways to allow me to control the audio channel (play only backing music or vocal or both) by using directshow (in vb.net).
Best Regards,