This Yamaha PSR A5000 has defective joystick. I tried three brand new keyboards and all have same problem. I opened a case with Yamaha Canada and so far no estimated time when this issue will be resolved and they said never heard about it before even though i see other reviews online. Please whoever has this problem, open case with Yamaha as I believe All A5000 have this problem and Yamaha should make a recall of it. I found this video on 鶹.com which describe the issue very well:
https://www.amazon.com/product-reviews/B0915H4SYH/ref=cm_cr_unknown?filterByStar=one_star&pageNumber=1