Your Accuslide cables are way, way out of adjustment. Surprised chain hasn’t come off the sprockets. In 2179.jpeg you can see on the green block the chain connection is at the very end of the adjustment bolt. My guess is the jam nuts weren’t tight allowing connections to loosen up. If you’re handy, study the manual and you can do it yourself. You’re lucky the motor is on top of slide. Mine is on the bottom and was very hard to adjust. From the factory the system comes with white foam anti vibration thingamagigers. All are missing except one which you can see in 2179.jpeg, so slide had been adjusted by someone in the past.
Sent from my iPad using Tapatalk