Originally Posted by james_uk
Maybe if you don't have the phone on silent or vibrate it does make a sound?
that's exactly it. If the ringtone (etc) is set to vibrate, the camera makes no sound, otherwise it makes a loud shutter noise. I tend to have it set to vibrate for calls etc. Suits me OK for the camera, but sometimes it can be a little weird wondering if it's actually taken anything or not. Good to know how to change this!