Need more information.

Compaq helped you? That's really good to hear but how do you mean, Alffe? They've never helped me. LOL

Down in the taskbar at the bottom of the page, usually next to the time/date, there is a symbol for the sound. Cone shaped.

If you Left click on the mouse you will bring up a few choices. Check in Volume Mixer. On my computer I have choice of Device and Applications. Check that you have those sliders in the positive.