I am using [M13ProgressHUD](https://github.com/Marxon13/M13ProgressSuite) to display a loader in my app. It works fine, but if I send my app to background while the loader is on, and return, the loader is frozen. Why is this happening? 

[![image](https://i.stack.imgur.com/HmhEW.gif)](https://i.stack.imgur.com/HmhEW.gif)

I'm adding the `hud` as:

```
_hud = [[M13ProgressHUD alloc] initWithProgressView:[[M13ProgressViewRing alloc] init]];
_hud.progressViewSize = CGSizeMake(60.0, 60.0);
_hud.animationPoint = CGPointMake([UIScreen mainScreen].bounds.size.width / 2, [UIScreen mainScreen].bounds.size.height / 2);
_hud.indeterminate = YES;
_hud.primaryColor = [UIColor whisperRed];
_hud.secondaryColor = [UIColor whisperRed];
((M13ProgressViewRing*)_hud.progressView).backgroundRingWidth = 2.0;
_hud.maskType = M13ProgressHUDMaskTypeSolidColor;
UIWindow *window = ((AppDelegate *)[UIApplication sharedApplication].delegate).window;
[window addSubview:_hud];

```

and showing it as:

```
dispatch_async(dispatch_get_main_queue(), ^{
        // Show an activity indicator
        [_hud performAction:M13ProgressViewActionNone animated:YES];
        [_hud setStatus:@"Connecting via Facebook"];
        [_hud setIndeterminate:YES];
        [_hud show:YES];
    });

```

Why is it getting frozen when app returns to foreground, even when I'm adding it on main queue?