Hyperdeck Studio HD Plus - Playback of one clip at a time?

I am trying to use my new HDSHD+ to play back lower third supers one at a time. We have multiple presenters, and I needed a way to get both an alpha and fill output, hence the HDSHD+. I have the unit playing back the Fill and Alpha channels as expected, but if there is more than one file (clip) on the SD card, it wants to play through all of them every time I hit play. How do I get the unit to only playback the next file in line?