Save mixer volume settings?

After I've entered a score, I go back and open the mixer and adjust the volume of the various instruments to achieve a pleasing balance. The score will play perfectly, the way I want it. However, if I close the score, and then reopen it (or quit Musescore and open the program later), the volume settings are not remembered. It seems the instrument volumes in the mixer revert to their default settings (i.e the volume settings that are there when an instrument is created/added.) Is there a way to have the settings saved along with the score?