I got my iPhone 4S and I think I have a problem with it. Sound when locking and unlocking is quiet compared with other iPhone 4S. I compared it with others and really is a little quiet. Other people have confirmed it too. Other sounds may be better. No pr

Turn the volume up.

Volume controls for functionality in iOS5 are seperate for each function (ringer, notifications, audio, calls, etc).

Yes, it's normal that Apple gives you control of the volume of sounds. For the lock and unlock sounds first unlock the phone, then press the UP volume button. This controls the ringer volume and the volume of click sounds.

My Iphone 4S has the same problem with lock/unlock sound, i had iphone 3GS and the sound was great, on this new Iphone 4S these sounds are very low. Is there any thing i can do? I read in some posts it might be a SIRI or IOS problem...

Have you turned up the volume with the buttons on the side of the phone, and removed the protective plastic that the phone ships with?

I have this problem too, but it is intermittent. Sometimes the lock/unlock volume will drop to barely-audible, even though in settings the volume slider hasn't changed. If I then move the volume slider, it fixes the problem and the lock sounds jump back to normal, but then later on the problem will happen again.

Forget the slider. Use the volume buttons on the side of the phone.

The volume buttons have no effect on the lock/unlock sounds when I'm experiencing the problem. The only way to fix it is to adjust the slider which somehow resets it.

You have to unlock it first, then use the buttons to increase the ringer volume, which is also the lock sound level. If that doesn't work either iOS is corrupt or your phone is broken.

Hi and thanks, this is indeed a bug or other software issue and not user error.

If it's a bug it is a bug unique to you. Neither of my iPhones has it.