Hardware problem topic

So, everytime i wave my phone around my ear i hear a sound at the back of the phone and makes me think that there's something broken or, detached.First, i thought its the vibration motor, but when i dissembled the phone, the motor seemed fine and well fixed there.I waved it again and the sound (i think) came from under the motherboard.I want to fix this problem because i can't use the vibrations.They work but, they sound like something is buzzing in there and it's not attached.