Saw this posted on Reddit and also have this issue (I reworked the writing to make a bit more sense): I have tried two iPhone 6s Plus phones and I have found that with the phone in my pocket the "Hey Siri" feature doesn't work. At first I thought it couldn't hear me, but now it looks like it's somewhat by design. It seems to be related to the new feature in iOS 9 that turns off the screen, when the proximity detector recognize a something close to it. Further research shows when the iPhone is facedown, the "Hey Siri" feature also does not work (also by design*). The problem is, this also results in the "Hey Siri" feature not working in my pocket. Unfortunately, I was hoping to be able to tell Siri to turn my lights on, while in my pocket, walking in the door at night. This bug/feature will prevent me from being able to do this. Would be nice if we could disable this temporary disable feature. Hey Siri-gate? * https://support.apple.com/en-us/HT204389 "You can turn off "Hey Siri" in Settings > General > Siri. In iOS 9 or later, you can also temporarily disable "Hey Siri" by setting your device face down."