<p>Somehow my iPhone Simulator is unable to play sounds.  First an app I'm working on using <code>AudioServicesPlaySystemSound()</code> stopped working.. I spent a while debugging this but sound is still working on the iPhone when I run the app on the device.  I get the same results with other iPhone apps such as the sample Crash Landing app.</p>

<p>I can't find a sound setting anywhere in the simulator or Xcode preferences.  I've tried resetting the simulator through "Reset Content and Settings" menu item to no avail.</p>

I've found sound to be very inconsistent in the simulator (2.1 SDK).  Sometimes it works, sometimes it doesn't.  Even when it does work, it's usually very choppy and distorted (when playing audio files such as mp3).
A few things to remember:
call
```
AudioSessionInitialize
```
as soon as your app finishes launching
set the
```
kAudioSessionProperty_AudioCategory
```
property for the session via
```
AudioSessionSetProperty
```
(with a value such as
```
kAudioSessionCategory_MediaPlayback
```
)
call
```
AudioSessionSetActive(YES)
```
Of course when all else fails, just run it on your hardware!
EDIT: Now that the 2.2 SDK has been released, I haven't had any problems with sound in the simulator. They must have fixed the bugs! I highly recommend you upgrade to the 2.2 SDK.