I've lost the Sound icon

[Basil Chupin]

The sound icon is gone from the upper taskbar  :-( .

Very recently this was brought up by someone and an answer was given to 
how to get it back (but it also brought something else with it). I 
cannot find that post even though I don't think I've deleted any messages.

Can anyone remember what has to be done to get the sound icon back, please?

BC

-- 
"I do not feel obliged to believe that the same God who has endowed us with sense, reason and intellect has intended us to forgo their use."
                                                                     Galileo Galilei