I am sure this is a misinstall issue and wants the Driver reinstalling I shall ask my colleague Dwight to have a look at it
Missing(or hidden?) Volume Icon Well, It is only Hidden when the sound is inactive... default setting (As you said) To Keep it on screen all the Time and you can inspect all the Main Sliders
Follow these instructions
1) Right click on the Start button and Select
Properties on the Menu
2) Click on the Taskbar Tab
Look down the Page and you can either Untick the Hide Inactive icons Box then press Apply then OK to reveal all the Icons or click the adjacent "Customize" Box?
2a)The "Customize" Box lead to a list of all the available Items in the Current items List and also several in the Past items list
3) Locate the Volume Item, it also shows you the Picture of the icon when it appears Note the script in the Behavior column It says
Hide when inactive Yes? Next Click on the Words.. and a little Menu appears Change the setting to
"Always Show" then press the OK button
Now look for the same Volume icon by the clock
"Double click" on it and the Master Volume Slider and Mute "All" box is on the far left of the Panel...Must be all the way up and the "Mute all " Tick box unticked for you to hear something OK ?
If you hear nothing now, then you'll need to reinstall the Realtek driver
This is the Retek Factory download page
http://tinyurl.com/4ne7so Tick the agreement "Box" and follow the links to the Driver you need, then select one of the buttons (A or B or C) to start the Download and save the file somewhere safe, when prompted (not very big) then click on the Folder when you are ready and it will install the latest driver for you ...Now does your sound Work? Max out sliders on the Volume Page if Need be?