Why do my servos make a loud buzzing noise when stationary?

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

Answer: A loud buzzing noise from servos when stationary usually indicates they are under continuous load or receiving a jittery signal. First, check your servo signal input—ensure your controller or receiver is providing a clean, stable PWM signal without rapid fluctuations. Use a servo tester or verify your transmitter settings. Second, confirm the servo isn’t mechanically binding or under too much load; physical resistance causes the motor to strain and buzz. If the servo is holding a position against a heavy or misaligned load, try easing the load or adjusting the linkage. Third, inspect your power supply; insufficient or noisy power can cause servo motors to buzz. Use a regulated 5–6V supply capable of delivering enough current for your servo. Lastly, some servos buzz slightly when holding position due to internal control circuitry, but loud buzzing usually points to one of the above issues. Addressing signal quality, mechanical load, and power supply will typically resolve the problem.