Over the past month, my iPhone 5's lock/wake button has slowly required a firmer and firmer press to work. Now, it barely works at all. I don't have an Apple Store nearby to take it in. Has anyone else had this issue? Is there a quick fix that would save me a long trip to my nearest Apple Store? The alternative of mailing it to Apple would leave me phoneless, so I'm looking to try fix it myself without invalidating the warranty first.