The MJX X101 is an affordable toy-grade quadcopter primarily designed to carry a camera. The standard package includes a battery/camera mount that is attached under the center of the canopy via screws and uses damping balls to compensate vibration. Although the design is sane, the way the battery cradle is mounted makes the whole construction vibrate to the horizontal axis; the vibration is especially noticeable when yaw is applied, as shown in the following video.
MJX X101 standard camera mount (without the mod)