class Class
    {
        private Queue<string> savedMessages;

        public bool Init()
        {
            savedMessages = new Queue<string>();
            ...
            consumer.Listener += new MessageListener(consumer_Listener);
            ...
        }

        private void consumer_Listener(IMessage message)
        {
            ...
                lock (savedMessages)
                {
                    savedMessages.Enqueue(message.Text);
                    Console.WriteLine("Queue now has: " + savedMessages.Count);
                };
            ...
        }



        public bool PeekIncomingNew()
        {
            Console.WriteLine("PeekIncomingNew");
            bool anythingNew = false;
            int count = 0;

            lock (savedMessages)
            {
                count = savedMessages.Count;
            };

            if (count > 0)
            {
                anythingNew = true;
                Console.WriteLine("Peek got new!");
            }
            else
            {
                Console.WriteLine("Peek, no new.");
            };

            return anythingNew;
        }
      }