Vacuum makes a loud high‑pitched whine during operation.

Safety first: Remove the battery before disassembling any components.

• Check for blockages: Ensure the cyclone and filters are clear and properly seated.
• Inspect seals: Listen for changes in pitch when pressing around the bin and seals while the unit runs (briefly, with battery installed). A change suggests an air leak.
• Assess motor noise: If the whine comes directly from the motor housing and is accompanied by vibration or burning smell, the motor bearings may be failing.
• Replace motor assembly: Motor bearing or fan issues are not serviceable; replace the complete main motor assembly.