What could be causing a furnace buzzing noise and how can it be resolved?

A buzzing noise from a furnace could be caused by a variety of issues, such as loose parts, a malfunctioning motor, or electrical problems. To resolve this, it is recommended to first turn off the furnace and check for any loose parts or debris. If the issue persists, it is best to contact a professional HVAC technician to diagnose and repair the problem.