Using AVAudioRecorder and AVAudioPlayer at the same time (or alternative ways of listening for sound and playing sound)

Is there any reason why this wouldn't w开发者_开发百科ork?

I'm testing for sound in the microphone and playing a looping sound effect as I'm registering sound.

On the iPod touch this seems to work fine - on the iPhone though the sound effect either doesn't play at all, or is very quiet.

Any ideas? Or any alternative?

Thanks

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for some reason had to put this code before I played the sound:

UInt32 sessionCategory = kAudioSessionCategory_MediaPlayback;
        AudioSessionSetProperty(kAudioSessionProperty_AudioCategory, sizeof(sessionCategory), &sessionCategory);    
        UInt32 audioRouteOverride = kAudioSessionOverrideAudioRoute_Speaker;
        AudioSessionSetProperty (kAudioSessionProperty_OverrideAudioRoute,sizeof (audioRouteOverride),&audioRouteOverride);

to stop it playing through the earpiece.