I got my iPhone 5 delivered on launch day and I've just noticed that when ANY audio is initiated on it there is a short popping, static-y sound, then a few seconds after the audio has stopped there is a second popping sound. This includes any audio, from music to keyboard clicks. There is also a slightly longer popping sound when opening the safari address bar. It only appears to occur with headphone use and I've reproduced the problem on all of my headphones and it drives me crazy when I have headphones in. I'm many hundreds of kilometres from an Apple Store and obviously supplies are constrained so any replacement will be quite delayed and I have found one other person on the Apple Support forums with this issue. Is it possible this is a software bug that may be fixed, or do I need to call Apple, because this is a really unacceptable problem.