12-04-2015, 11:42 AM
Right-click on empty area of panel and choose Panel -> Panel Preferences -> Items (tab). Look to see if item "Notification Area" is listed. If it's not, add it to the panel to restore missing network and sound items. If it is, select it and hit the "Edit" button along right side of window. Look to make sure sound and network things are not marked as "hidden".
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