code.m

    NSError *categoryError;
    NSError *activationError;
    AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    BOOL successfulCategory = [audioSession setCategory:AVAudioSessionCategorySoloAmbient error:&categoryError];
    BOOL successfulActivation = [audioSession setActive:YES error:&activationError];

    NSLog(@"Category: Error: %@. Success: %@", categoryError, [NSNumber numberWithBool:successfulCategory]);
    NSLog(@"Category: Error: %@. Success: %@", activationError, [NSNumber numberWithBool:successfulActivation]);
    
    AVPlayerItem *item = [[AVPlayerItem alloc] initWithURL:[[NSBundle mainBundle] URLForResource:@"trax"
                                                                                   withExtension:@"mp3"]];
    player = [[AVPlayer alloc] init];
    
    [player replaceCurrentItemWithPlayerItem:item];
    [player play];

console output.log

2015-07-13 16:02:28.912 AudioStreamingApp[5938:1005780] Category: Error: (null). Success: 1
2015-07-13 16:02:28.913 AudioStreamingApp[5938:1005780] Category: Error: (null). Success: 1