AVPlayer crashes after multiple time play video from local directory

Question

When i click my local video url and present Viewcontroller and Play video in AVPlayer.Play 14-15 times and Player crash.Avplayer showing like

- (void)viewDidLoad
{
   [self PlayVideoinPlayer:_videoURL];
}

-(void)PlayVideoinPlayer:(NSString *)URL
{
      NSURL *fileURL = [NSURL fileURLWithPath:URL];

     _Avcontroller=[[AVPlayerViewController alloc]init];
      asset = [AVURLAsset URLAssetWithURL:fileURL options:nil];
     anItem = [AVPlayerItem playerItemWithAsset:asset];
     _avPlayer = [AVPlayer playerWithPlayerItem:anItem];
     [_avPlayer addObserver:self forKeyPath:@"status" options:0 context:nil];
     self.Avcontroller.view.frame = self.view.bounds;
     [self.Avcontroller setPlayer:_avPlayer];
    _Avcontroller.videoGravity=AVLayerVideoGravityResizeAspectFill;
     [self.view addSubview:self.Avcontroller.view];
     [self.view addSubview:self.Avcontroller.view];
     [_avPlayer play];

    CMTime interval = CMTimeMake(1, 1800);
   __strong __typeof(self) weakself = self;
    playbackObserver = [_avPlayer    addPeriodicTimeObserverForInterval:interval queue:dispatch_get_main_queue() usingBlock: ^(CMTime time) {
    CMTime endTime = CMTimeConvertScale  (_avPlayer.currentItem.asset.duration, _avPlayer.currentTime.timescale, kCMTimeRoundingMethod_RoundHalfAwayFromZero);
    if (CMTimeCompare(endTime, kCMTimeZero) != 0)
    {
        // double normalizedTime = (double) avPlayer.currentTime.value / (double) endTime.value;
        //NSLog(@"--------->>>>%@",playbackObserver);
    }
    int CurrentSecond=[[weakself getStringFromCMTime:_avPlayer.currentTime] intValue];
   _avPlayer.rate=1.0f;

 }

Anyone have solution.? Please help me.Thanks