AVAudioPlayer is not playing in Background when iPhone is locked

Question

Actually i fetching the songs from Documents Directory.

I referred this Link:- http://www.raywenderlich.com/29948/backgrounding-for-ios , But it wil

Answer 1

Are there other audio/video apps currently running on your device? Some of them that also use AVAudioSessionCategoryPlayback can interrupt your audio session.

How it is said on Apple Developer:

By default, using this category implies that your app’s audio is nonmixable—activating your session will interrupt any other audio sessions which are also nonmixable. To allow mixing for this category, use the AVAudioSessionCategoryOptionMixWithOthers option.