Why are my servos buzzing 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 under constant load or receiving a jittery control signal. First, check your servo’s neutral position by disconnecting the signal wire; if it stops buzzing, the issue is likely with the control signal. Use a servo tester or your controller to ensure the signal is clean and stable. If you’re using a microcontroller, verify your PWM signal frequency and pulse width are correct for your servo model.

Second, inspect the mechanical setup. Make sure the servo horn isn’t physically blocked or under strain, which can cause the motor to fight against resistance and buzz. If the servo is trying to hold a position against a heavy load, consider upgrading to a higher torque servo or adding a gear reduction.

Finally, check your power supply. Insufficient or unstable voltage can cause servos to buzz. Use a regulated 5–6 V supply capable of delivering enough current (usually at least 1–2 A per servo). Following these steps should reduce or eliminate the buzzing noise.