Vacuum makes a high‑pitched whistling noise during use.

Safety first: Turn off the vacuum and remove the battery.

• Locate the sound: Reinstall the battery and briefly run the vacuum while listening closely (keep fingers and hair away from moving parts) to identify the area of the whistle.
• Inspect seals: Remove the dust cup and inspect the perimeter gasket. Ensure it is clean, undamaged, and seated correctly.
• Check pipes and nozzle: Look for small objects lodged in the nozzle or pipe that may cause turbulent airflow.
• Inspect for cracks: Examine the extension pipe and plastic body for hairline cracks. Replace any cracked components.