We bought a little nice red sixth-generation iPod Nano to my sister Elvira as a Christmas present. Two months later, the power button got stuck and it was no longer possible to turn it on or off. She discovered that plugging in to the USB cable would wake the iPod up so it could be used, but it was not very convenient, to say the least. A quick internet search revealed many cases like this, with no solution but sending it back to Apple. If there are many units built like this out there, I guess many more will fail with time. I thought I might be able to repair it myself.
When I opened the iPod and reached the back side of the power button, it found the shim that actually presses the switch was held in place with double-side sticky tape. With use and probably with the help of high temperatures, the shim slides to the border of the button, away from the switch underneath. This is why the button no longer actuates the switch and does not give the tactile feedback, feeling loose or stuck.
After removing the shim and the double tape, I cleaned the back button surface and the shim with acetone. The goo traces are very sticky but it is very important to remove every bit and leave the surfaces clean and dry. The fibers of the Pec-Pad cloth I used are clearly seen in the picture but are invisible to the naked eye :
With a minuscule drop of two-part metal cement, the shim is placed in the middle of the button, where it should be:
The volume buttons use the same shim and same double-side tape and although they may be fine, it is a good idea to fix them now. This three pictures show them before, with the shim and tape removed, and finally, cemented:
I wonder how they went for this cheap double-tape method of fixing the shim in place after all the amazing solutions and technology that have gone into the Nano. I guess future revisions of the device will be built differently. This procedure is simple in theory but requires steady hands and a good loupe/microscope. It is impossible to make yourself an idea of the scale of the buttons from the photos, the shims are two milimeters long. Just disassembling the Nano to reach the buttons is not easy to do without breaking someting. If you are not sure if you are capable of doing this, you probably are not, so it may be a good idea to send it to Apple.