At the bottom right of the computer screen is the the speaker icon. It remains with a small red X on the speaker icon if your speakers are muted or not plugged in. My speakers work fine with any other devise such as a mp3 but not with my computer. I click the mixer and nothing happens. But get this, when I right click the volume icon and chose "Open Volume Mixer" the volume control pops up but with no bars to adjust the volume levels. In the top left of the bar it says "No audio devise installed". I went to control panel, then hardware & sound, then sound, and found under playback tab I found "Realtek High Definition Audio" with a green small check on the icon next to it. I know I have the right playback device selected because realtek is the only one there and it is what my computer uses. Do I need to re download realtek? I really have no idea whats goeing on with my computer and its depressing I cant hear my friends or my music over the internet because my computers volume thingy is messed up 
