The lens in your camera is a mechanically operated feature. The noises you're hearing are normal movements of the plastic gears inside the lens. These noises are not something to worry about as long as your camera's lens is functioning normally.
the noise is a problem because it can be heard in video playback, making it useless. i would like to know how people have solved this problem. i already purchased an external rode video microphone and attached it to the top of the camera - but unfortunately i also picks up the grinding sounds because it is close to the camera. i want to be able to shoot handheld without carrying another microphone or needing an additional person to carry a microphone. if there is someone who found a mic that works, tel me !
Use a hot shoe extension for your cam and level the mic signal down on the cam. I had this problem too with my noisy dmc fz 1000 and the rode video mic. There are many cheap solutions on Amazon. With this, the noise is nearly gone.
