Vacuum makes a high-pitched whistling noise during use.

Safety: Turn off and remove the battery.

• Localize the sound: Run the vacuum briefly and listen around the bin, wand joints, and floor head to find the leak source.
• Inspect gaskets: Check rubber seals on the bin, cyclone, and joints for tears or deformation.
• Check for cracks: Look for hairline cracks in the dustbin or cyclone housing.
• Replace damaged parts: Install new gaskets or a replacement bin/cyclone assembly as needed.