Since I have to do remote desktop control over a lot of computers using Mac OS or warn of an upcoming update, I began using Mac’s speakers to address the users. Obviously it is useless to speak to a user whose speakers are muted.. so I decided to change the system volume via CLI.
sudo osascript -e "set Volume 0"
Maximum volume :
sudo osascript -e "set Volume 10"
Volume at 50% :
sudo osascript -e "set Volume 5"