said by Nezmo:
My phone, running 6.1.3 is sitting on the desk in front of me. Screen was off/locked. Without me touching it Siri came up and froze.
In general I've had Siri issues with 6x. I cannot get Siri to launch when the phone is connected to a dock connector in my car. But at least she launches on her own on my desk. LOL
Out of curiosity, what kind of car do you have?
I can get Siri to activate in my car via the SYNC system's microphone w/o issue (of course I have to use the home button on the iPhone 5 to wake Siri up)