I am running the samples shipped with the Paho Java client: http://git.eclipse.org/c/paho/org.eclipse.paho.mqtt.java.git/
Wether it is their own example, or a standalone hello world Paho demo from other sources, or even in conjunction with Spring Integration, the client somehow happens to receive a message more than one time, if its payload exceeds 200MB (this is not an exact figure, since I tested by gradually increasing the payload by 5MB message by message).
My broker is Mosquitto. I tried all QOS configurations, Still the same.
Remarkably, this does not happen when working with the Paho Python library, using the same setup. So my environment (network, broker, publishing client, etc.) should be fine.