Sound on any digital camera is a crap shoot.
Manufacturers of digital cameras will spend some money on projects that improve the capture of still picturesl.
They treat video/audio as an afterthought and spend as little as possible on it.
Sound is one of the places they will settle for second best.
Because it will be expensive to make it good.
Auto Focus and zoom motor noise is quite common as is wind noise when you take the camera outdoors.
They do poorly when trying to record live music that is even close to loud.
If you want a camera that does everything well, you need more money.
Canon says they will have such a camera for Christmas.