Check the speed for Outer Wall, Inner Wall, and Infill with the recommended printing settings as below.
Factory reset the printer to apply the default Acceleration settings.
a. Connect the printer to Snapmaker Luban software with the USB cable.
b. On the Console panel, input M502
and press Enter.
c. On the Console panel, input M500
and press Enter.
Check the Acceleration settings in the slicer. The recommended max Acceleration is 10000 mm/s2.
See here to tension the belt.