Hi Steve,
That is strange! Let me ask you a few questions.
1. Did it work properly before and the problem with multiple emails just started? If it just started, can you tell me any recent changes that were done to the site like maybe a DNN upgrade, a change in hosting, upgrade to the module?
2. In Admin, Event Viewer, please choose Debug Info and see if you can find the same email event firing more than once.
3. Is there only 1 email address that's experiencing this problem? If you change the EMAIL TO address, does the problem continue?
Thanks,
Candace