Dispatch async was added to the STOMP library of OTDT
With this new additional configuration setting the processing speed and load could be controlled depending on the appropriate amount of incoming messages (Triggers) and the runtime of the Actions.
In some situations the processing speed of OTDT Actions may take much longer or differ significantly. If you realize, that this starts to affect the dispatching olf STOMP messages - specially if in an high available environment - then you should set async dispatch to true.