subscription.cs

var settings = ConnectionSettings.Create(); //.EnableVerboseLogging().UseConsoleLogger();

using (_conn = EventStoreConnection.Create(settings, new IPEndPoint(IPAddress.Loopback, DEFAULTPORT)))
{
    _conn.ConnectAsync().Wait();

    var bufferSize = 10;
    var autoAck = true;

    CreateSubscription();

    _conn.ConnectToPersistentSubscription(STREAM, GROUP, EventAppeared, SubscriptionDropped, User,
        bufferSize, autoAck);

    Console.WriteLine("waiting for events. press enter to exit");
    Console.ReadLine();
}