Has anybody experienced the iPhone off switch not working all the time.

Question

I have an iPhone 5, it's about 16 months old and it has experienced an annoying issue.  The off button does not work all the time, sometimes I have to press it multiple times and other times it just works.  The worst case is when it does not work at all, very frustrating.  I didn't expect this type of issue for a phone that is not even a year and a half old.
I did some searching on the internet and there are 2 schools of thought, the first is that this is a hardware fault and Apple know about it but won't admit it because it would cost them too much to repair/replace phones with the issue.  The second school of thought is that it is a software issue and a backup/reset/restore will fix it; I tried doing this but it did not resolve the issue.
Further digging seemed to suggest that it was really a hardware fault and the only option was to get a refurb from Apple for a ton of money, not cool.
Anyway, if anyone has any more information that could help me resolve this issue I would greatly appreciate it.
//*eggbox23

Answer 1

@diesel vdub, thanks for your suggestion, I setup an appointment with the Genius Bar and found out in about 5 minutes that everything I have read up on so far is true.
Firstly the technician admitted that there is a sporadic fault on the iPhone 4s and iPhone 5 switches, something to do with the design of the switch that included a rubber element that rolls up (whatever that means) and causes the switch to fail. He then indicated that the iPhone 5s does not have the issue because the switch has been completely redesigned.
Since I was stupid enough to not take out the extended warranty the only options he gave me were to purchase a new phone or to get a refurb for $269, not cool. Why would anyone think that a phone would not work correctly for 2 whole years when the phone only cost about $600!
Since I have about 7-8 months left on my phone contract I am not prepared to pay for either option.  I find it amazing that a phone can develop this type of issue in such a short time and then expect the customer to pay for their failures.  Apple supposedly sells a very high quality product for a very high price, looks like they have taken a step back from this philosophy.
I am disappointed in the options that he gave me (I don't blame the technician) but I suppose I expected more from Apple in terms of quality and service.
//*eggbox23