The easiest fix may be something you have already tried and that is to check the volume level. Do you see a speaker icon in the system tray (lower right hand corner)? If yes, you can click on it to adjust the volume. If no, try the following:
1. Click on Start
2. Click on Control Panel
3. Double click on Sound
4. Click once on Speakers and then click on the Properties button.
5. Click on the Levels tab.
You can try adjusting the volume there. Please let me know what you see if this does not help.