Everytime my phone vibrates it makes this loud noise from inside that sounds like a weird cracking noise or something help!!

Okay so I noticed a week or two ago that there was something lose on the inside of my iPhone 5s and ever since then when my phone vibrates sometimes there is this weird noise. It sounds almost like a cracking noise from the inside or a weird electrical noise. I think something is wrong with the vibrating part. Does anyone know if this is fixable or what it is?