Possible Causes
- Resonance in a trim component, for example NVH insulating cloth against speaker grill mesh
- Lack of retention of interior and exterior trim panels
- Labels vibrating against trim/nearby components
- Nearby modules vibrating against trim/BIW
- Mechanical failure of internal speaker component
- Loose harness/harness clips
- Loose trim
- Loose items in or around speaker
- Loose fixings
- Debris inside speaker