i've already had the top case replaced for creaking once, and now its started again a month or two later. each time it happens on the bottom left part of the case, and creaks if you even gently touch it. ridiculously, i've also discovered if you just press harder on that corner of the case, it appears to "flatten out" the creak (although it comes back after a while). so i can only assume there is next to no structural strength in this chassis design. and to be clear, i've been using macbook pros for years and never had this issue on any of the previous models, nor am i "abusing" the laptop. it spends almost all its time on a desk. has this cropped up for anyone else??