DIAGNOSIS Hair and fiber accumulation on the main brush ends and the brush chamber axles. This is a normal maintenance issue, especially with long hair or pet hair.
FIX Perform weekly manual maintenance. Flip the robot over and unlock the brush cover. Remove the main brush. Use the provided cleaning tool to cut and remove hair wrapped around the brush ends. Also, clear hair from the two silver axles inside the brush chamber. Reinstall the brush, ensuring it clicks and spins freely.
IF THAT DIDN'T WORK The brush may be damaged or unbalanced. Inspect the rubber fins on the main brush for tears or warping. A damaged brush will not spin correctly even when clean. Order an official replacement main brush. Ensure it is the specific V-shaped brush for the S8 series.
HEADS UP Do not run the robot with a severely tangled brush. The motor will overheat and may trigger an error 12 (Main Brush stuck). Regular manual cleaning is required; the auto-empty dock does not clear brush tangles.