That technician is mistaken. It is not the sleep wake button. It's the vibe motor. Its not a defect its just how the part was designed. It occurs in just about every model of iPhone there is. Go to the local apple store and tap the backs of all the iPhones. Some will respond louder than others. It is not a defect and I seriously doubt it causes you much distress unless you walk around tapping your phone with it close to your ear.
I have this same issue with the sleep button. Just got denied any type of service or replacement because it's "within manufacturing tolerances". He also mentioned it is probably the new vibration motor in iPhone 5s - I told him to hold the button and see if it rattles. It did, but still no dice. Psssh! "Manufacturing tolerances" of a maraca.
I'm actually on my third iPhone 5 now (original bought in November 2012). I finally upgraded from a pristine 3GS.
First one was fine, no rattle, until about 1 month of (extremely delicate and careful) use. Heard a slight tinny rattle coming from the camera area. Annoying, but didn't think too much of it until around the same time, all photos started to have a big dust blob (as in, dirty sensor) near the centre of every shot. That was too much for me (every shot ruined) so I took it into an Apple Store where they replaced it right before Christmas.
Didn't hear the second unit rattle right away (might have been because it was loud in the store). Even if it didn't, within a couple days I did notice it more and more. No camera dust problem though. However, what was really starting to trouble me was that the rattle seemed to get worse. It was a tinny (not a thud-like) rattle as if a screw was loose. It didn't seem to matter if you'd try the camera and lock focus (as some have suggested), if you tapped the phone it would still rattle. I was worried that another dust problem might occur and called AppleCare again.
They told me that this was "normal" and part of the autofocus mechanism within the camera. This would be somewhat reasonable, but then once the focusing was engaged and locked, it shouldn't keep rattling. What was more troubling about this unit was that it seemed to get horrible reception (as in, constantly losing signal strength until eventually no signal) or switching from 3G to LTE to even Edge (I'm on Rogers). Would rarely stay in LTE. Now, my office building has window tint film which is apparently metallic and messes up reception, but we also have several cell repeaters throughout the building. For whatever reason, I could look at my phone in my office drop from 3 to 2 to 1 to no service, within a couple minutes. This was with iOS 6.0.1, and 6.0.2.
The reception issue was enough of an issue that I was escalated to a manager and it was agreed that I should get a new unit. I also mentioned that this phone also had a slightly raised ridge on the upper plastic to metal seam on the back of the phone (the one right under the camera). It was hard to see, but you could definitely feel it if you ran your finger over it. I only mentioned this because it was one of the first things I noticed versus my first phone, and my finger tended to land along that seam when holding it during a call. Looking closely, it almost looked like the plastic part was raised toward the centre of the phone, making it higher than the metal part. The bottom seam also didn't feel exactly smooth, but not as bad as the top seam.
I happen to work at an R&D facility with lots of cool equipment, including a measuring microscope that can measure down to the micron scale (i.e. 0.0001 mm). According to the original PR of the iPhone, it was supposed to have some amazing tolerances. I looked under the scope and sure enough, the seam edges (top and bottom) were not exactly parallel to each other; the bottom of the plastic side of the seam was not in line by about 30 microns (i.e. ~0.03 mm) in the centre of the phone compared to the sides. Also, the seam itself was about 30 microns narrower at the centre of the phone versus the seam width at the sides. This would mean there is at least a 30 micron tolerance (well, +/- 15 microns I guess) not matching up well along this seam, if not up to 60 microns combined. I remember their PR video saying that their manufacturing tolerances were something on the order of 7 microns, so this would indicate a potential order of magnitude difference.
In any case, I'm on my third phone (just received it yesterday). The seams are much smoother (I haven't measured yet), the reception is consistent (3 bars in my formerly "no service" office!), and yes, it still rattles. What those without the rattle don't seem to realize is how annoying it is. When you're on a call and ANY notification comes with the phone on vibrate, you can definitely hear a random sounding tinny rattle. If it's on my desk, same thing (since it resonates through the desk). If it was more regular sounding or had more of a pattern to it, I'd be more apt to believing it was a "normal" situation, but the "loose screw" type of sound is troubling. Of course, a colleague's iPhone 5 doesn't rattle, so to me, it is not impossible to have a non-rattling phone. Plus, my first phone didn't rattle, but did progressively get worse.
Not sure if I'll keep this one, but I'll be paying attention to any news about this issue. Hopefully Apple will address this somehow and not keep sending out rattling phones!
I have an iPod touch 5g too and I can clearly hear the rattle sound in every condition. So
1. iPods don't have vibra, so it can't be the vibra motor!
2. even when focusing there's always this annoying sound
3. my first iPod touch 5g was absolutely silent even if I hadn't care of it (no covers, ecc)
4. the sound is still there even if I hold the lock button
A friend of mine have an iPhone 5 and he has this sound too, but it's very very very annoying because I can hear it every time I place it on every kind of surface starting from when I gently place it on a table to when i leve it on my pillow. I had a lot of phones with autofocus but none of them ever rattled!
The 5 I just started using is rattling after about 1 month of use. I did not notice it until now so I checked my wife's 5 and her phone does not do it. She has had her phone for about 6 months. I have had 4 other iPhones several which I still use for music and none of them do it. Some posters have suggested that it is the vibration motor but the weight on the motor should not be hitting anything the cause a noise. The motor just spins with a weight attached to the shaft that is offset and causes the motor to vibrate. A clicking noise is not a normal thing it indicates a part is loose, if it is a normal design feature they should ALL do it and the manufacturer would be able to tell you why they designed that into the phone. I am going to take my phone into Apple it is still under warranty. I'll post the results of my trip.