Feature description:
Add an option to protect the settings with a password.
Problem solved:
Kids (or wife) breaking the app by “accidentally” fiddling with the settings.
Brought benefits:
Symfonium could be used on a kid’s device as a simple frontend to play music or audiobooks.
Other application solutions:
I hear Yatse has a similar feature… 
Additional description and context:
Should there be some recovery option in case the password gets lost? Maybe some file that could be imported? Well, in that case I can also store the password in a file, and maybe I should be punished if I don’t remember the password…
Screenshots / Mockup:
+----------------------------------------+
| Enter password to access settings. |
| Password: ___________________ | OK | |
| Note: if you forgot the password, |
| you are screwed and need to reinstall. |
+----------------------------------------+