Hi everyone, I have a strange question for you all. I recently purchased a MacBook Air 11" 2013 model as there have been good sales on them in Australia. My first MacBook Air had very noticeable hard drive noise. Anytime there was hard drive read/write activity the noise goes again. It is the exact same mechanical noise that an old netbook of mine use to make. This makes no sense though as the MacBook Airs use flash storage with no moving parts. The noise is definitely timed with hard drive activity though and is the same as the mechanical noise from many hard drives. I returned the first MacBook for this as I thought it was strange. The replacement had no such issue but wasn't level. It literally didn't sit flat on a desk and rocked whilst you typed. Hence that one was also returned. I'm now on my third 11" and I'm back at square one with the exact same mechanical hard drive noise. It's not a noise you could hear in most places but certainly working in my study or in a library it's noticeable and annoying. What is going on? Thoughts on this? The unit is otherwise perfect besides this. Great solid feel unlike the last one and a really nice bright white screen. Runs fast etc. I've owned many 13" MacBook Airs before and have a 15" Retina and have never heard hard drive noise on a flash machine. This is not the fan type noise other users have noted. Definitely regular mechanical noise during hard drive activity. To test for yourself it's really easy to hear when booting up the machine in a quiet room.