Hi, the vibrations can sometimes be due to tensor tympani muscle spasms. There are three tiny ear bones in the middle ear (the area on the other side of the eardrum) with muscles (the stapedial and tensor tympani muscle) that are attached to them. Like any muscle, they can go into spasm and rapidly twitch (myoclonus). When this happens in the ear, it will cause the eardrum to vibrate like a drum, resulting in a clicking or even a machine-like sound. The muscles in the throat and palate (the tensor veli palatini muscle) can also be contributory.
If your symptoms persist, you may need to consult an ENT specialist. Muscle relaxants may help with this condition. Regards.