A mysterious overlay

My wife’s iPhone 5s has a strange fault. In Messages, the message box has a grey box overlaid on it, with three zeros at the right side. You can type with the keyboard but you can’t see what you are typing. Restarting the phone temporarily fixes it. What’s going on? Should I ask O2 to swap it? Mike Riley

The phone is fine. The 0:00 display is the timer for an audio message. The last update to iOS seems to have introduced a bug that triggers this feature inappropriately – possibly the algorithm that detects when you lift the phone to your ear is now a bit too sensitive.

There are three workarounds. The first is to double-click the Home button and swipe up on Messages’ thumbnail, which clears its temporary data. When you open the app again, the timer box will be gone. Secondly, before you type anything in the message box, you’ll see a microphone icon instead of the Send button; hold a finger on this to get rid of the timer overlay.

Finally, for a more permanent solution, go to Settings > Messages > Audio Messages and switch off Raise to Listen.