Hello Rongzhong, I have the issue that only one joint (13) of all joints is moving. The batteries are sufficiently charged and all motors are connected to the NyBoard, and I believe the wiring is correctly (even if it isn't more than one motor should move?). When I try to calibrate the servos no. 13 is the only one that rotates, same goes for when I type in a command. When I run Nybble.io I always get "FIFO overflow! Using last reading!" in the serial monitor. I also tried different settings on the onboard potentiometer. Thank you for your time and help!