Oops , there is already a mention for that > https://wiki.ubuntu.com/SoundMenu#%E2%80%9CMute%20All%E2%80%9D/%E2%80%9CUnmute%E2%80%9D
Oops , there is already a mention for that > https:/ /wiki.ubuntu. com/SoundMenu# %E2%80% 9CMute% 20All%E2% 80%9D/% E2%80%9CUnmute% E2%80%9D