You mention that you have "Just reinstalled the O.S."

• Did you also install the "hardware drivers" for your computer?
• Does the "HP Pavilion DV1659US" need to have hardware drivers installed in order for you to get full functionality out of it?

Computers are different. They have different types of CPU, hard disk, graphics, networking and audio.  With some computers, some of these devices demand that they have the correct version of their own software in order to work properly or at all. When you install the operating system, (eg. Vista), you install lots of software that allows you to get the computer doing lots of things well. However, there might be some features that want their own software before they work properly. Did your computer some with a disk that talks about "Device Drivers" or something like that? Did you you install that straight after reinstalling Vista?

Numerous times I've helped people in the following manner:

1. Make sure their speakers / headphones are working (by using my laptop)
2. Plug their speakers / headphones back into their computer
3. Go into "Sounds and Audio" area of control panel / computer settings on their computer.
4. Have a look around to see whether I get the feeling that perhaps the sound controls are "disabled".
5. I might even try the [Test Hardware] button which gives me a pretty good clue as to whether things are working or not.
6. Install the sound drivers for their computer (either from the disk that came with their computer or downloaded from the internet)
7. Go back into "Sounds and Audio" area of control panel / computer settings.
8. Expect to see that the sound controls are now  "enabled". And if so...
   
9. Try playing a music file, (eg. from the "Sample Music" folder in the "My Music" folder)

Good luck.