losing MIDI volume

In a particular song I’m working on, something changed so that when I run Nuendo in “cycle” mode, the volume of most of the instruments drops to zero when the section repeats. This is happening with MIDI instruments and I have no audio in this song so I don’t know if that’s affected also.

If I choose “reset on stop” in the preferences, I’m able to get the volume back once I stop the recording but this is only a band aid fix.

This behavior doesn’t appear to be happening in other Nuendo projects.