So I've had my S350 for a few years, and I got into making and composing my own orchestrations and stuff. I can export my 6 part multipart tracks into midi files fine on my USB, but when I go to play it, tracks seem to disappear. Does anyone know why this happens? I literally know next to nothing about midi, so I cannot figure out why tracks don't show up in further output after saving it to my USB. Thanks!