Missing Thousands of Messages using DynamicData Listener

Hi All, I am experiencing an issue where my Listener is missing messages when I use DynamicData and configuring QOS seems to have no effect. I have an application that subscribes to many topics with the purpose of reading all the messages and persisting an XML and binary version for each (dont ask why). We have a publisher pushing a test set of 69,000 messages into the DDS for us to consume. Each message is on one of ten Topics each with a single Type. We have subscribed to the Topics, registered Types, created Topics and subscribed to them with a DataReader and Listener. If all I do is record the count of times on_data_available() is invoked we get 69,000

public void on_data_available( DataReader reader ) {
    // record count
    // DO NOTHING MORE -- ALL OK
}

If I use a DynamicDataReader to take messages and get the DynamicData from the sequence and stop there, we get 69,000 messages coming through.

public void on_data_available( DataReader reader ) {

    // record count

    DynamicDataReader dynamicDataReader = (DynamicDataReader) reader;
    try {
        dynamicDataReader.take(dynamicDataSeq, sampleInfoSeq, 
                ResourceLimitsQosPolicy.LENGTH_UNLIMITED, 
                SampleStateKind.ANY_SAMPLE_STATE, 
                ViewStateKind.ANY_VIEW_STATE, 
                InstanceStateKind.ANY_INSTANCE_STATE);
        
        for (int i = 0; i < dynamicDataSeqSize; ++i) {

            SampleInfo info = (SampleInfo) sampleInfoSeq.get(i);
            if ( info.valid_data ) {

                DynamicData dynamicData = (DynamicData) dynamicDataSeq.get(i);

                // DO NOTHING MORE -- ALL OK 
            }
        }

    } catch ( RETCODE_NO_DATA noData ) {
        reuturn;

    } finally {
        dynamicDataReader.return_loan(dynamicDataSeq, sampleInfoSeq);
    }
}

As soon as I try to get the Type from the DynamicData and read the name or do stuff with it the number of messages we get, and the number of times on_data_available() is called, drops to ~500 messages of the 69,000

public void on_data_available( DataReader reader ) {

    // record count

    DynamicDataReader dynamicDataReader = (DynamicDataReader) reader;
    try {
        dynamicDataReader.take(dynamicDataSeq, sampleInfoSeq, 
                ResourceLimitsQosPolicy.LENGTH_UNLIMITED, 
                SampleStateKind.ANY_SAMPLE_STATE, 
                ViewStateKind.ANY_VIEW_STATE, 
                InstanceStateKind.ANY_INSTANCE_STATE);
        
        for (int i = 0; i < dynamicDataSeqSize; ++i) {

            SampleInfo info = (SampleInfo) sampleInfoSeq.get(i);
            if ( info.valid_data ) {

                DynamicData dynamicData = (DynamicData) dynamicDataSeq.get(i);

                TypeCode typeCode = dynamicData.get_type();   // <--- THIS

                String typeName = typeCode.name();

                // get XML and binary
            }
        }

    } catch ( RETCODE_NO_DATA noData ) {
        reuturn;

    } finally {
        dynamicDataReader.return_loan(dynamicDataSeq, sampleInfoSeq);
    }
}

We noted that the Default TopicQos and DataReaderQos was configured as

Reliability 'BEST_EFFORT_RELIABILITY_QOS'
Acknowledgment 'PROTOCOL_ACKNOWLEDGMENT_MODE'

So we have changed that to 

TopicQos topicQos = DomainParticipant.TOPIC_QOS_DEFAULT;
topicQos.reliability.kind = ReliabilityQosPolicyKind.RELIABLE_RELIABILITY_QOS;
topicQos.reliability.acknowledgment_kind = ReliabilityQosPolicyAcknowledgmentModeKind.APPLICATION_AUTO_ACKNOWLEDGMENT_MODE;

and

DataReaderQos dataReaderQos = Subscriber.DATAREADER_QOS_DEFAULT;
dataReaderQos.reliability.kind = ReliabilityQosPolicyKind.RELIABLE_RELIABILITY_QOS;
dataReaderQos.reliability.acknowledgment_kind = ReliabilityQosPolicyAcknowledgmentModeKind.APPLICATION_AUTO_ACKNOWLEDGMENT_MODE;

With no effect... still ~500 messages. Clearly the amount of time it takes to call dynamicData.get_type() is impacting on the performance of the on_data_available() method and we're missing messages. If setting the QOS doesnt resolve this what can? Any assistance you can offer will be gratefully recieved Cheers Al