I got a MBA 11" when it came out. It was good for a week, then it started to creak whenever I would pick it up, move it around while using it on my lap, or lean my wrists on it. From the beginning, the right speaker would rattle with certain sounds/frequencies, which was easily reproducible with some songs and the message received/sent sounds in Adium. I looked at iFixit's tear-down, and suspected it was the battery that was the cause. The individual cells looked taped to the big black plastic support bracket, and I guessed that when there was slight twisting of the unit from said actions above, the tape would get stuck/unstuck and create the creak noise. As for the speaker rattle, I suspected that the sound would rattle the batteries and its stickiness to the tape. iFixit finally put for sale the screwdriver to open the MBA, which I ordered (and it arrived from CA to NYC in 2 days). I took off the bottom cover and removed the battery. With just slight twisting of the battery unit, I could easily create the creaking noise and make lots of it, and it did indeed was caused by the tape holding the batteries in place getting stuck/unstuck with movement of the battery. So using plain old clear 3M Scotch tape, I placed single strips of tape over the four corners on one side of the battery (circled in the first picture), and then on the other side, I taped every single seam outlined in red in order to keep the battery in place. After, when I twisted the battery, it barely made any noise, though I was unable to completely eliminate the noise. I forgot to take an after pic, but just imagine single strips of 2cm wide clear 3M scotch tape covering every seam. It looks ugly but.... Put it all back together, and......MBA NO LONGER CREAKS! And the speakers no longer rattle either. I suspect Apple has or will fix the problem easily by using a stronger tape to hold the battery cells in place or securing the cells better in some other way.