ios 8 uitableview stuck/hang/freeze when scrolling to the end of table

I really need helps from you. I'm trying to load some data (about 50 records) to UITableView. But it got frozen/hang while scrolling to the end of the tableview. I did try to log which row is displaying. When I scroll down, the log show the row 1... 49 is display then it starts over with row 42.

This is the .h file:

@interface VDevicesViewController : UIViewController<UITableViewDataSource, UITableViewDelegate>
{
    NSString* access_token;
    NSMutableArray* data;
    NSMutableArray* deviceNotGoodData;
    NSArray* _deviceTypeList;
    NSArray* _thumnailArray;
    DAPagesContainer* pageContainter;
    UITableView* tableAllDevices;
    UITableView* tableNotGoodDevices;

    int currentPage;
    UIView * footerView;
    UIActivityIndicatorView* indicator;
}
@property (strong, nonatomic) IBOutlet UIView *myView;

-(void)refresh;
@end

this is the .m file

- (void)viewDidLoad
{
    [super viewDidLoad];
    CGRect screenRect = [[UIScreen mainScreen] bounds];
    [self.myView setFrame:CGRectMake(0, 32, screenRect.size.width, screenRect.size.height)];

    // Do any additional setup after loading the view
    data = [[NSMutableArray alloc] init];
    deviceNotGoodData = [[NSMutableArray alloc] init];
    pageContainter = [[DAPagesContainer alloc] init];
    [pageContainter setPageIndicatorImage:[UIImage imageNamed:@"up_arrow_gray"]];
    [pageContainter setTopBarBackgroundColor:[UIColor colorWithRed:24.0f/255.0f green:177.0f/255.0f blue:214.0f/255.0f alpha:1]];
    pageContainter.pageItemsTitleColor = [UIColor whiteColor];

    [pageContainter willMoveToParentViewController:self];
    pageContainter.view.frame = self.myView.bounds;
    pageContainter.view.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
    CGFloat width = self.myView.frame.size.width;
    CGFloat height = self.myView.frame.size.height - 50;
    CGRect tableFrame = CGRectMake(0, 0, width, height);
    UIViewController* allDeviceContoler = [[UIViewController alloc] init];
    tableAllDevices = [[UITableView alloc] initWithFrame:tableFrame style:UITableViewStylePlain];
    tableAllDevices.delegate = self;
    tableAllDevices.dataSource = self;
    tableAllDevices.tag = 0;

    NSString* allDeviceTitle = [NSString stringWithFormat:@"All Devices(%@)", [[NSUserDefaults standardUserDefaults] valueForKey:KEY_DEVICES_USED]];
    allDeviceContoler.title = allDeviceTitle;
    [allDeviceContoler.view addSubview:tableAllDevices];

    UIViewController *notGoodDevicesControler = [[UIViewController alloc] init];
    tableNotGoodDevices = [[UITableView alloc] initWithFrame:tableFrame style:UITableViewStylePlain];
    tableNotGoodDevices.delegate = self;
    tableNotGoodDevices.dataSource = self;
    tableNotGoodDevices.tag = 1;

    NSString* uncompliantDevices = [NSString stringWithFormat:@"With Issues(%@)", [[NSUserDefaults standardUserDefaults] valueForKey:KEY_DEVICES_UNCOMPLIANT]];
    notGoodDevicesControler.title = uncompliantDevices;
    [notGoodDevicesControler.view addSubview:tableNotGoodDevices];

    [self.myView addSubview:pageContainter.view];
    [pageContainter didMoveToParentViewController:self];
    pageContainter.viewControllers = @[allDeviceContoler, notGoodDevicesControler];
    currentPage = 1;
    access_token = [[NSUserDefaults standardUserDefaults] valueForKey:TOKEN_ACCESS_KEY];
    _deviceTypeList = [NSArray arrayWithObjects:@"desktop", @"laptop", @"phone", @"tablet", @"server", @"router", @"switch", @"vm", nil];

    _thumnailArray = [NSArray arrayWithObjects:@"device_desktop_small", @"device_laptop_small", @"phone", @"tablet", @"device_server_small", @"router", @"switch", @"device_vm_small", nil];

    [self GetDevices:[NSNumber numberWithInt:currentPage]];
    indicator = [[UIActivityIndicatorView alloc] initWithFrame:CGRectMake(screenRect.size.width/2.0, 40, 37, 37)];
    [indicator startAnimating];

    [self.myView addSubview:indicator];
}

#pragma mark - TableViewDelegate
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    if (tableView.tag == 0) {
        return [data count];
    }
    else if (tableView.tag == 1)
        return [deviceNotGoodData count];
    return 0;
}

// Row display. Implementers should *always* try to reuse cells by setting each cell's reuseIdentifier and querying for available reusable cells with dequeueReusableCellWithIdentifier:
// Cell gets various attributes set automatically based on table (separators) and data source (accessory views, editing controls)

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {

    static NSString* cellIdentitifier = @"TableCell";
    UITableViewCell* cell = [tableView dequeueReusableCellWithIdentifier:cellIdentitifier];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellIdentitifier];

    }

    NSArray* flexData;
    if (tableView.tag == 0) {
        flexData = [NSArray arrayWithArray:data];
    }
    else
        flexData = [NSArray arrayWithArray:deviceNotGoodData];


    if (flexData.count > 0) {
        if (indexPath.row < ([flexData count])) {
            // add data here
            NSLog(@"%ld", (long)indexPath.row);
            VDeviceObject * deviceObject = [flexData objectAtIndex:(indexPath.row)];
            cell.textLabel.text = deviceObject.hostname;
            cell.detailTextLabel.text = deviceObject.username;
            cell.detailTextLabel.textColor = [UIColor colorWithRed:180.0f/255.0f green:180.0f/255.0f blue:180.0f/255.0f alpha:1];

            if ([deviceObject.numberOfIssues intValue] > 0) {
                cell.backgroundColor = [UIColor colorWithRed:247.0f/255.0f green:247.0f/255.0f blue:247.0f/255.0f alpha:1];
            }

            cell.imageView.image = [UIImage imageNamed:[_thumnailArray objectAtIndex:[deviceObject.deviceType intValue]]];
        }
    }

    return cell;
}

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    [self performSegueWithIdentifier: @"ViewDetail" sender:indexPath];
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return 65;
}
-(void)GetDevices:(NSNumber*)page {
    if (access_token == nil || [access_token isEqualToString:@""]) {
        return;
    }
    NSError* error;
    NSData * devicesData = [VTabBarViewController sendSyncGetRequest:[NSString stringWithFormat:@"%@?access_token=%@&limit=%@&GroupBy=issues&page=%@", GEARS_API_GET_DEVICES, access_token, @"50", page] errorCode:error];

    NSString* errorString = [[NSString alloc] initWithData:devicesData encoding:NSUTF8StringEncoding];
    NSString* stringCode = @"Requested page number exceeds limit";
    if ([errorString rangeOfString:stringCode].location != NSNotFound) {
        return;
    }
    NSMutableArray* list = [NSJSONSerialization JSONObjectWithData:devicesData options:NSJSONReadingAllowFragments error:&error];
    for (int i = 0 ; i<[list count]; ++i) {
        NSDictionary *dict = [list objectAtIndex:i];
        NSString* hostName = [dict objectForKey:@"hostname"];
        NSString *machine_type = [dict objectForKey:KEY_MACHINE_TYPE];
        NSNumber* numberIssues = [dict objectForKey:KEY_TOTAL_ISSUE];
        NSDictionary *userinfo = [dict objectForKey:KEY_USER_INFO];
        NSString* username = [userinfo objectForKey:KEY_USER_NAME];
        NSString* hwid = [dict objectForKey:KEY_HWID];
        VDeviceObject *object = [[VDeviceObject alloc] init];
        object.username = username;
        object.deviceType = [self deviceType:machine_type];
        object.numberOfIssues = numberIssues;
        object.hostname = hostName;
        object.hardwareId = hwid;

        [data addObject:object];
        if ([object.numberOfIssues intValue] > 0) {
            [deviceNotGoodData addObject:object];
        }
    }
    NSLog(@"On page: %d", currentPage);
    //[tableAllDevices reloadData];
    //[tableNotGoodDevices reloadData];
}

This is the gif image to demonstrate the problem I've got (I did try to reduce the size but its quality is so bad) http://ift.tt/1zBy4Co

Thank you...

Update: I try to add 'UITableView' by storyboard, connect with the 'IBOutlet', it works. So maybe I did something wrong with the table :(