My home button hasn't been very responsive for the last week or two. Maybe half the time I hit it, nothing happens. It's an iPhone 4 and it's still under warranty. There hasn't been any liquid damage. Does Apple typically replace a phone for this reason? Has anyone had any experience with this problem? The home button is still in tact and still clicks, it just doesn't consistently work. I know this isn't an unheard of problem, just curious if I should bother taking it into the store. thanks.