iphone making random calls

I think I found the problem. First off, I rarely use bluetooth headset with this particular AT&T phone. But though none active, I have several paired up with it. Last night while the random calls were happening, I deleted all recent calls from the phone except my home phone number. I turned off the phone went to bed. I turned on the phone in the morning, sure enough within 5 minutes it started calling my home phone. I look at the iPhone, it showed no bluetooth connection icon, while I was looking at it, it made another call to my home phone while the previous call is still active. While I was fussing with the iPhone to figure out what's wrong, I received a call, while I was on the call, the iPhone put that call on hold and started calling my home phone again. While it was doing all that, it revealed that there is a Bluetooth connection with a VOX headset. I gathered all my Bluetooth headsets both from the house and from the car, all of them were either dead (no battery juice) or completely off. So, for some strange reason iPhone thought that I was connected to a Bluetooth headset that is not even on, and not only that it thought I was actually pressing the dial button on that ghost Bluetooth headset. In order to be 100% sure that the issues are not caused by an actual headset, I looked at my other iPhone to see if I ever paired this VOX headset with it. As it turns out that I had, so I tried to connect to the VOX headset with no avail. So, I am sure that the iPhone was connecting to a ghost headset.

How I solved it: I removed all paired Bluetooth devices from the affected iPhone. That’s it. Hope this would help someone.