Question Issue Finding Open UDP Port?

Hey guys, I'm trying to find an available open udp port on iOS and it's giving me some issues.

Code (CSharp):

1.  
2. private static readonly IPEndPoint DefaultLoopbackEndpoint = new IPEndPoint(IPAddress.Loopback, port: 0);
3.     private int FindAvailableUDPPort()
4.     {
5.         using (var socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp))
6.         {
7.             socket.Bind(DefaultLoopbackEndpoint);
8.             return ((IPEndPoint)socket.LocalEndPoint).Port;
9.         }
10.     }

This works on Windows, Android, and OSX. However on iOS with XCode building in Release will result in the following error occuring (the last before the app freezes)

Warning: Libinfo call to mDNSResponder on main thread

At this point the app also freezes. This error however is highly unfortunate to google and doesn't result in much.

However, if I were to build this as a Debug schema in XCode, it will run perfectly fine... Anyone have any ideas to point me in the right direction?

 

silence sadness bump