Hi everyone, I have a MBPr that is approaching 3 years old. The A and D keys make plastic crackling noises when pressed. They even tend to hang up after being pressed (only briefly) and make a noise on the way back up. I assume the plastic mechanism under the key may be in need of a replacement. The keys work fine, and nothing was ever spilled on the keyboard - no liquids or food. What should I do to fix this? It's still under the 3 year Apple warranty, but I hesitate taking this to a store for such a minor problem. I never got the best impression from the "techs" at Apple stores. Should I purchase some replacement hinges and do it myself? I see the whole key is $4.95 on some sites. Was hoping to find them cheaper. I've also never popped a macbook key off myself, but from Youtube it looks simple enough. Any input is appreciated!