I just unboxed my new 13" retina and i thought I heard a rattle inside the case. In trying to replicate it I noticed that if I hold the macbook with the lid open and sway it side to side or tilt it laterally back and forth it sounds like the keys are loose. It's basically making a faint noise as I move it back and forth. Is this normal? Kinda what is being reported here: https://discussions.apple.com/thread/5529000?tstart=0 Just wanted to hear from anyone else who has a new RMBP 13"