Yes. If it is a digital servo, it is probably something in the linkage causing a bind. They start to hum, sing, complain that they are under a load. If it is an analog, it may be a bind also, or a defective servo.

Disconnect the serov lead and feel the movement of the arm. Is it sticking or hard to move? Is it clicking as you move the arm. If yes, fix the servo or replace it.. Replace would be the best bet. For the cost of a $25 servo, it just isn't worth the cost of the whole plane, engine, and radio equipment.

Just like old food in your frig, when in doubt, throw it out.

Don