MAJOR BUG - Phone calls auto speaker & dial FaceTime

I know never to download a major S/W update for two weeks so this is partially my fault.

I have friends having the same issue so it is not a user issue. During a phone call, at any time, the phone conversation goes silent and when you look at the screen, it's trying to FaceTime someone. End the FaceTime and then the phone is in speaker mode. Take it off the speaker and you can go back to the conversation - with about 5 seconds missing!

There was something similar happening in a long ago version where the iOS wasn't recognizing the phone up to the face and leaving the screen active. I suspect it could be a similar issue this time but don't know.

Who else? They won't fix this unless they know it's widespread.

Is there a particular duration to the call that makes this happen? I had a 20 min conversation with my iPhone 4 running iOS 7 this morning and didn't have any problems. I've used it for a bit before through Bluetooth in my car and have not had any problems..

I took a conference call from it yesterday, which lasted 2 hours. No issues whatsoever on an iPhone 5.

I just had another call for about 30 mins with American Express and had no issues with it either. I went from speakerphone (while on hold) for the first 10 minutes to off speakerphone when speaking to the rep..

It generally happens within the 1st minute. I have had every iPhone since the first one and have only had this issue once before which was eventually recognized and fixed by Apple in an update. It happened before because the screen wasn't being locked when the phone was in use up to the ear. I don't know if it's the same this time but I do know it's repetitive with myself and a couple of friends who have experienced it. I also have friends who have not experienced it so there may be some settings that allow it?

The problem doesn't occur in going back and forth between speakerphone and it is not occurring 20 minutes into the conversation. It always happens in the first 3 or 4 minutes and generally within the first minute, Swipe to answer, put it to the ear, start having a conversation and then all of a sudden, it goes silent, FaceTime is activated and dialing, End FaceTime, take it off speaker or sometimes mute, rejoin the conversation.

Frustrating.