Waze forum

there are 2 ways to mute and un-mute the sound in waze.
1. through the main menu.
2. through the apps settings panel.

The bug is that these two settings aren't affecting one another.
i.e. sound can be muted through the menu and still show as enabled in the settings panel.

Btw, this was tested on Android, Samsung SII device

The Main Menu mute mutes all sounds, which includes nav instructions and alerts. The Sound menu navigation "None" just affects nav audio. It is working as expected and designed at this time.

Think of it like the sound on your computer: you have a sound volume and a sound mute. Mute doesn't change the volume setting, because when you unmute, it goes back to the previously selected volume level.

Trinary mute button will be available in the next version. Can't tell if it works properly yet due to not enough testing time. Here's how the button states look at the top of the main menu. Pretty clear IMO.