OK heres the info on what I've done. I wanted to learn Marvin Gaye's "Ain't That Peculiar" Nice piano riff I could play live while singing it. I loaded the MP3 on the thumb drive and put it in the BK9. Sounded terrible. Tried the center track mute function and it sounded worse.
As a point of referance went out last Friday to the Elks Lodge where they have entertainment . They had a guy doing a DJ thing and singing to tracks that sounded like they were not full Karaoke but he just used a Center Cancel function on his laptop. You could still hear some of the original voices. Didn't sound good to me but they love this guy there. Even asked the guy who books the entertainment what he thought of this guy and he was all over him "you know he won three DoWop contests and he plays in Vegas "
So much for the general publics taste.
My idea was , hey I can do this on my BK9.
BK9 manuel says to use Wav tracks not MP3's. Went online and found a converter. Put the new version on the Thumb Drive and now it doesn't show up at all.
Should I try Midi tracks where I can cancel out a part?
This is new territory for me so forgive my lack of knowledge with it.

Thanks in advance