The crossfader of KORG ZERO 4 has 3pin connector. But usual crossfader has 4pin connector. An example is Vestax crossfader or Pro X Fade etc. In this time, I made 3pin-4pin converter connector and confirm system operation. This movie is the evidence!! http://homepage.mac.com/yamamo2shun/Yamamo2andRiesBlog/files/category-english.php