first time it is working, then go back and come again, play pause not working.

gistfile1.m

- (void)viewDidLoad
{
 NSURL *urlmusic=[[NSURL alloc]initFileURLWithPath:[[NSBundle mainBundle]pathForResource:@"music" ofType:@".mp3"]];
   
   
    player = [[AVAudioPlayer alloc] initWithContentsOfURL:urlmusic error:nil];
   
    player.numberOfLoops = -1;
   
    [player setVolume:1.0];
    [player prepareToPlay];
[super viewDidLoad];
        // Do any additional setup after loading the view, typically from a nib.
}
-(void)music:(UIButton *)close
{
    if ([[NSUserDefaults standardUserDefaults]stringForKey:@"musicbutton"] == nil)
    {
        [player stop];
     
          [musicbutton setImage:[UIImage imageNamed:@"off_button"] forState:UIControlStateNormal];
        [[NSUserDefaults standardUserDefaults] setObject:@"on" forKey:@"musicbutton"];
        [[NSUserDefaults standardUserDefaults] synchronize];
     
       
         NSLog(@"off");
        NSLog(@"player value%@",player.description
              );
    }
    else
    {
       
        [musicbutton setImage:[UIImage imageNamed:@"on_button"] forState:UIControlStateNormal];
        [[NSUserDefaults standardUserDefaults] setObject:nil forKey:@"musicbutton"];
        [[NSUserDefaults standardUserDefaults] synchronize];
        [player play];
       
         NSLog(@"on");
    }
   
   
}