I have an 1100 IS Digital Elph. I just pulled it out to check, and there does seem to be a lot of noises that I would describes as clicks and sort of grinding noises. Its always done that, its normal. Obviously without hearing your camera, its hard to know if we're talking about the same sort of noises.
Also I *think* I read in my manual somewhere that you can turn off the sounds- most aren't actually made by the camera but its programmed to make them so it "sounds" like a camera, I think. My manual is extremely hard to find stuff in though, so I couldn't locate that bit when I looked. If your camera does that you could try it and see if it helps you figure out whats going.