Resume AVAudio session after interruption

Question

Issue:

My application's audio is not resuming after an interruption (such as phone call or when I use other applications). This issue happens when my application is already in the background state before the interrupt occurs.

Code to handle interrupts:

- (void)handleInterruption:(NSNotification *) notification{
    if (notification.name != AVAudioSessionInterruptionNotification || notification.userInfo == nil) {
        return;
    }

    NSDictionary *info = notification.userInfo;

    if ([notification.name isEqualToString:AVAudioSessionInterruptionNotification]) {

        if ([[info valueForKey:AVAudioSessionInterruptionTypeKey] isEqualToNumber:[NSNumber numberWithInt:AVAudioSessionInterruptionTypeBegan]]) {


            NSLog(@"InterruptionTypeBegan");

        } else {
            NSLog(@"InterruptionTypeEnded");
            dispatch_after(dispatch_time(DISPATCH_TIME_NOW, 0.1 * NSEC_PER_SEC), dispatch_get_main_queue(), ^{
                NSLog(@"playing audio");

               self->_audioPlayer.numberOfLoops = -1;
               [self->_audioPlayer play];

            });
        }
    }
}

In Xcode console, I see logs in the following sequence but no audio is played:

1. InterruptionTypeBegan
2. InterruptionTypeEnded
3. playing audio

I would appreciate any suggestions and thoughts on this topic. Thank you.

EDIT:

I have noticed the same issue with many online music streaming apps such as Saavn and Spotify.