The projector can be muted using one of the following settings -
1. OSD > System setup > audio settings > mute
2.. Mute key on remote
The mute function will reset to default (Off) when the projector is restarted, which means audio will be on.
Therefore, if you wish to mute the projector permanently, please turn the audio volume down to 0. Volume levels do not reset for power cycles or restarts.