If you have had your phone for about 16 months, I presume it will be a '1st gen' iPhone 4 like mine. I also have intermittent problems with my home button. My problem started about 8 months ago and whilst it hasn't got any better, it hasn't got any worse, thank goodness.
I have been told that this is a known problem with the 1st gen phones and have been told that it can be sent away which will take about 7-10 days to get it back to me with no guarantee of a fix (as it's intermittent, it may behave whilst the engineers play with it to find the fault) or I can book an appointment with my local Apple Genius Bar, again with no guarantee of it being fixed or the phone being swapped. It may be worth ringing Apple Support and having a word, but they'll probably advise you to get a Genius to have a look at it anyway but they may be able to advise you if it can be swapped (although with it being over 12 months old, I doubt this may happen as there is only a 12 month guarantee on iPhones??).
In a world where everything is a copy .... I remain an original
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