title: Cocoa OSX app hangs on dispatch_async
body: <p>My app fires off a thread specifically for checking the status of a process. It fires every 5-10 seconds:</p>
  
  <pre><code>if(!monitorTask){
          MYLog(100,@"Monitor task is dead");
          return;
  }
  dispatch_async(monitorTask,^{ // fuckup here
          MYLog(150,@"...Checking iTunes");
  </code></pre>
  
  <p>However it also seems to hang there every so often:</p>
  
  <p><a href="https://i.stack.imgur.com/15iWi.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/15iWi.png" alt="enter image description here"></a></p>
  
  <p>Any clues how to fix/catch this? The app is beachballing but "running" in Xcode just fine - stuck on this instruction:</p>
  
  <p><a href="https://i.stack.imgur.com/5Dgtx.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/5Dgtx.png" alt="enter image description here"></a></p>