It works 80% of the time. Sometimes requires a second press (giving me Siri instead of a screenshot), or if it's being cranky, it'll take a good 5 or 6 clicks until it wakes up or puts the phone to sleep. It's been like this for about 6 months, not enough to warrant a visit to the store, but enough to be annoying. I have one day to either keep it or replace it with a refurbished device of unknown quality. What should I do?