Has anyone ever tried playing glissando on the SP4-7? (if you don't know, glissando is running your hand down the entire keyboard really fast). If you have an SP4-7, please try it and let me know your results. There is a delay from after you finish running your hands down the keys, and when you actually hear the sound. Is this normal for this keyboard? Or is there something wrong with mine? I have a video I can email as an example if you're curious. Thanks