New guy here....

I was thinking of dabbling in Music like I did back in the late 80s and I just dusted off my Atari ST and found my Band In the Box disk.....


It works. And I'm connecting to an old Kawai K4


And to make things really silly, I have connected my Nintendo Rock Band 3 MIDI Guitar control and playing some rythm using the Atari's MIDI IN as a THRU reaching the Kawai K4 and playing Guitar sounds along side Band In The Box's Bass and Drum accompaniment


SO HERE IS MY ISSUE: Something is happening to the guitar controller playing thru the Atari ST with Band In the Box....there is some funky noise when I strum all the strings....like an unwanted load percussion or orchestra note

Any ideas?