Sometimes there's no sound on notifications after iOS9 update
So I updated my iOS devices (iPhone 6Plus, iPad 4 and iPod Touch 5) with the new iOS 9 on 17th September and since then I have noticed a weird thing. For most of the apps such as whatsapp, viber, Facebook Messenger, Gmail and some games (for which I have set the notifications as active), there's no notification sound but still the notification comes up on the screen. This happens even with the native messaging app (whether I send a text or iMessage). When there's another notification from the same app, then notification plays the sound or at times the sound stutters for multiple notifications from same app (e.g.: whatsapp group texts).
So anyone else facing the same issues? Does anyone know a solution? I have tried restarting, restoring and updating my devices to iOS 9 again and the mute buttons on my iPhone and iPad weren't ON while facing the issues. The volume is at max level.
I guess its already time for Apple to release iOS 9.1 fixing the issues.
iOS devices that were updated:
iPhone 6Plus - 128GB
iPad 4 - 64GB
iPod Touch 5 - 16GB
iPhone 6 Plus, iOS 9