Why is there a buzzing sound inside the car?

[RicardoLee]

The possible reasons for a buzzing sound in the vehicle include: uneven tire tread blocks or severe tire wear; impending damage to the wheel hubs of certain wheels, with the most direct symptom of hub failure being an increase in the buzzing sound as the vehicle speed rises, which then maintains a constant volume after reaching a certain speed. Below is additional information: 1. Requirements for in-car noise: According to the "Technical Conditions for Safe Operation of Motor Vehicles" issued and implemented by the former National Bureau of Technical Supervision on January 1, 1998, the noise level inside passenger vehicles should not exceed 82 decibels; the noise level near the driver's ear should not exceed 90 decibels. If the noise inside the car is below 60 decibels, it is considered acceptable, with 40-60 decibels being the range for normal conversation. 2. Sources of in-car noise: 1. The vehicle's engine is a source of noise, which can be generated and transmitted through the front fenders, hood, firewall, and exhaust pipe. 2. Road noise occurs when the vehicle is driving at high speeds, caused by wind cutting in and the vibration of the chassis during driving, as well as the impact of sand and gravel on the road against the vehicle's chassis, which also generates noise.