Why do servos buzz loudly when stationary?

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

Answer: Loud buzzing from servos while stationary usually means they are holding position under load or receiving a jittery signal. First, check your servo's signal input: ensure your controller or receiver is providing a clean, stable PWM signal without noise. Using a servo tester can help isolate this. Next, verify the servo isn’t mechanically binding or under excessive load, which makes the motor strain and buzz. If your servo is holding a position against resistance, slight motor vibrations are normal. To reduce buzzing, try gently adjusting the neutral position or trim settings on your transmitter. Also, consider lowering the holding torque if your setup allows it. Finally, ensure your power supply is stable and provides sufficient current; voltage drops can cause erratic servo behaviour. If all else fails, swapping the servo for a known good unit can confirm if the issue is with the servo itself. Regular maintenance and correct setup will keep your servos quiet and smooth.