How to stop DITA automatic IDs

Hi, FM2015, Win7. I have structured FM files with a root element of <topic>, but are not DITA. While authoring, the DITA feature set is automatically adding IDs to all elements that have an ID attribute. I know it is DITA doing this because when I change the ID prefix in the DITA options, the IDs change. I unchecked the "Auto-Add IDs..." option, no change (the IDs aren't mandatory anyway).

Can I make this stop without turning off the DITA clients entirely?

Russ