Bug: Raise to Speak sensor for Siri remains on whenever the screen is active - regardless of Siri Raise to Speak Setting (enabled or disabled).
After updating to iOS 6 (via iTunes - not OTA), I noticed that my battery was taking quite a bit of a hit. Granted I was checking out the new features but aside from a very short call, nothing major in the way of activity.
I had also noticed that Siri sounded quite a bit different with iOS 6 (10A403) than with 5.1.1 (9B206). Not only did the Siri Voice change but also the responses vary between the two iOS versions.
Example: What is the weather like in Alaska?
iOS 5.1.1 response:
Here's the forecast for Juneau, Alaska through Monday
iOS 6.0 response:
Here's the weather for Juneau, AK through Monday (note: Siri does not say "Alaska", instead Siri says 'A-Kay'
With iOS 6, Siri sounds more robotic. After looking at speech rate settings and comparing between the two versions, I could find nothing different. I decided to post a video and this is where the Siri bug became interesting and tied into the battery drain with iOS 6.
Remember with 5.0.1 we saw a hit on battery drain and one of the fixes was a fix to the proximity sensor (http://hottipscentral.com/could-siri-be-hurting-iphone-4s-battery-this-little-li ght-might-mean-something/). Well, it appears this bug is back in iOS 6. When I went to do the video, I noticed that my 4s had a flashing light near the earpiece. It remained on continuously. The only time it would stop flashing was when the phone was locked and the screen inactive. As soon as I hit the lock button to bring the phone out of lock, the sensor would begin to flash again.
Give it a shot, hold up your iPhone to a webcam and see if your result is the same.
Submitting this to Apple via the feedback form. Please do the same if you are seeing the same behavior.