MQTT Receive Creates Own Topics

Hi,

When I connect to Aretmis with an MQTT test step, a new ReadyAPI-specific topic is created.  I can send to it, but I'd like my test step to use the existing topic that's known by other subscribers.  The is the configuration specifies only "mytopic" as in the screenshot below.  In the second screenshot, notice the ReadyAPI-generated topic.

Thanks in advance,

Carl