If you don't have speaker on Icon Tray (bottom right), means you have missing drivers for your Audio and if so you can't here any adio from your system. To find out whether you have missing driver or not, follow these steps:
- Click on Start -> Control Panel
- Double Click on system icon
- Click on Hardware
- Click on Device Manager.
Now the device manager window will appear. See carefully in the components list, if there is any component with yellow mark, then you have missing driver.
If you have missing driver then after installing the correct driver will fix your problem.
If you don't have driver tell me your manufacturer and model no. I will give you the link or you can find on the manufacturer's site.
If any question just