cannot disable startup/shutdown notifiction

[nopfsense]

Hello, I am having trouble disabling the startup /shutdown notification, I Navigate to SYSTEM/ADVANCED/NOTIFICATIONS then tick the disable the startup/shutdown beep options.

scroll to the bottom and click save. the page jumps to the top but doesnt show a notification that chagnes have been saved.

If i leave the page and go back the sound option is not selected.

This is particularly vexing as there is no jumper on the MB or option in the BIOS to disable the onboard speaker.

Can anybody shed any light on this?