For real, does the device have a camera or microphone? I don't know what else could be using that much data. A quick Google seems to show they don't have built

For real, does the device have a camera or microphone? I don't know what else could be using that much data. A quick Google seems to show they don't have built in voice control. That's just a huge amount of data if it's not sending some sort of media back home. Could always be poor programming for logging or something, but that wouldn't be my first suspect.