My volume icon located in the notification area of the bottom tool bar, disappears mysteriously. When I notice it is gone a check of the task bar properties, shows it "grayed" out with no check mark. I must restart the PC in order to place the check , which restores the icon. Not a big deal but irritating. A forum search touched on this subject did not help. Any ideas on a permanent fix? OEM OS MS Windows Vista Home Premium Edition 64 bit, PC HP m9457c. Incidentally, I have contacted HP support on other PC issues and found the service to be POOR.