I see a lot of reports of things like this. No matter which phone you buy..HTC One, S4, iPhone or whatever...the risk is there that you may get one that has a flaw or many flaws. That's the reason for exchanging or returning them. And if you return it, who's to say that the new phone you get won't have any issues.
I know we all pay the big bucks to have the best phone and expect everything to work flawless, but stuff happens.
I'm sure people that buy the next big phone..whether it be the S4 or iPhone 5s, will be going over it with a fine tooth comb...to find any little issue they can find...and it'll be another thread just like this one .