For the first time ever when using an iPhone I experienced a strange frozen lock screen. I was able to use Siri by holding down the main button, I was able to slide up and down but not use any of the option and I couldn't unlock my phone or slide to power off. Need to do a lock+home button shutdown. Is this an issue with iOS 7.0.3? This is the first time it's happened to me but I'm a little worried this might become a recurring issue?