Robot vacuum is very loud during operation; grinding or rattling noise from brush area.

Safety first: Turn the robot OFF and flip it over.

• Remove main brush: Open the brush cover and take out the brush.
• Inspect for damage: Look for cracks, missing bristles, or bent sections. Check end caps and bearings for wear.
• Clean housing: Remove any stones, glass, or hard debris from the brush channel.
• Test without brush: Run the robot briefly without the brush installed. If the noise disappears, the brush or its bearings are the cause.

Solution: Replace the main brush and, if needed, the main brush bearing blocks or motor module.