Apple released an iOS update on Thursday, though it's a tiny change.
iOS 6.1.4, which appears to be available only for the iPhone 5, updates the "audio profile for speakerphone."
The software weighs in at 11.5MB and is available by way of the over-the-air iOS software update tool, and in iTunes.
Apple's last iOS update was 6.1.3, back in March. That update fixed a lock screen security bug and improved some Apple Maps features for users in Japan.