IPhone IOS avaudiorecorder sound recording with avplayer sound is small

When avaudiorecorder is used for recording, avplayer has a low playing sound, especially on mobile phones Before iPhone 4. I don't know whether the sound is small or the playing sound is small.

Stackoverflow:

1) recording time

[[Avaudiosession sharedinstance] setcategory: avaudiosessioncategoryplayandrecord error: Nil];

[[Avaudiosession sharedinstance] setactive: Yes error: Nil];

Uint32 dochangedefault = 1;

Audiosessionsetproperty (kaudiosessionproperty_overridecategorydefatospeaker, sizeof (dochangedefault), & dochangedefault );

2) playback time

Avaudiosession * audiosession = [avaudiosession sharedinstance]; nserror * err = nil; [audiosession setcategory: avaudiosessioncategoryplayback error: & err];

That's all.