I've been getting a lot of "unknown" callers for about a year now. On more than one occasion, it's been at the most inconvenient times. Like when I'm in the middle of a web search or something. I've often thought it was odd that it almost always happened when I was actually using the device. Today, it was super obvious. I hadn't touched my phone since I unplugged it from the charger when I got up. Four hours later, I unlocked the screen to send a text and within 30 seconds, I get an "unknown" call. It's got to be something talking to an outside source, telling it that the phone is awake. Is there any way that I can prove that and find the culprit? Thanks.