The answer to 'why is my ceiling fan buzzing noise' is that a buzzing noise from a ceiling fan is usually caused by a loose or faulty component. This can be due to a problem with the motor, the blades, or the mounting hardware. The buzzing may also be caused by electrical issues, such as a loose connection or a problem with the wiring.
To troubleshoot the issue, start by inspecting the fan for any loose parts or connections. Check the blades to make sure they are securely attached and balanced. If the motor is the issue, you may need to replace it. Electrical problems may require the help of a professional electrician, as they can be more complex to diagnose and fix.