Hey, I'm new here so I want to share some experience with you guys. Recently I got a new 15 inch RMBP, but then I noticed there was squeaky noise when I hold my macbook and pressed the bottom lid. So I brought it to Apple Store and made an exchange. However, the problem still existed. Then I tried to figure it out why.. so I opened up the bottom lid by unscrewing the screws, did nothing, then put screwed it back. NO MORE squeaky noise!! Hope this helps!!!