At times a doorbell may actually sound off or have a buzzing sound. Sometimes the ringing mechanism sticks. The chime box is not always the problem but is at the easiest point to disable. Quieting a sticky doorbell is a very simple job and needs only a screwdriver.
Remove the cover from the door chime. The cover is made of plastic and usually has two snaps that are holding it in place. Pull the cover to one side and it should pop right off.
Locate the two wires that control the chime mechanism. They should be to one side or underneath the chime hammer. This set off an electromagnet that pulls the strike hammer to the chime bar.
Loosen both of the screws that control the electromagnet. Do not take them all the way off. Pull the two wires off of the screws. This will disable the chime mechanism. Replace the cover.
Be sure that no power is coming from the doorbell button, which controls the flow of electricity to the chime box.