Why do my servos buzz loudly even when stationary?

Question: Why do my servos buzz loudly even when not moving?

Answer: Loud buzzing from a servo when it’s not moving usually means it’s struggling to hold its position. This can happen if the servo is receiving a continuous signal telling it to maintain a certain angle under load, or if the power supply isn’t sufficient. First, check your power source; servos often require a stable 4.8–6V supply with enough current (at least 1–2A per servo). Next, ensure the servo isn’t mechanically obstructed or overloaded, as this causes the motor to strain and buzz. Try disconnecting the servo horn and see if the buzzing stops—if it does, the load or binding is the issue. Also, verify your control signal: if the pulse width is jittery or incorrect, the servo will hunt and buzz. Use a servo tester or a clean PWM signal from your controller. Finally, if the servo is old or damaged, internal gears or the motor may be faulty, and replacement might be necessary. Checking these steps should reduce or eliminate the buzzing noise.