Volume drop-off when synthesizer delay module (Zita1) is ON

Reported back in October 2015 at https://musescore.org/en/node/83911

Play the attached file. Make sure Zita1 delay is ON in "View > Synthesizer >Master Effects > Effect A." Adjust the master effects "Output" to "Mix" (say). Note the subjective volume level and the peak levels in the volume meter.

Now close the program, re-open it and play the same file again (without touching any settings). You should hear a definite drop-off in volume and the peak levels in the volume meter are lower. You can restore this volume by making any adjustment, no matter how small, to the master effects "Output."

Close and reopen the program, and play the file again. The volume is again lower, and, again, you have to adjust the master effects "Output" to restore it.

If you turn the Zita1 delay OFF and repeat the experiment, the problem disappears.