My volume went out and yes I checked the mute/un-mute button.

I had this mute problem and found that unpluging it for 1 to 2 min. and the problem cleared.

Try pressing the mute (speaker symbol with diagnol line) or just press up/down volume button

Press the mute button again. If that doesn't work, then press the volume-up button until you can hear the popping noise of the volume adjustment.

Double-click the "volume control" icon, to open the "sound mixer" control. Move all the sliders to "maximum", and remove any "mute" check-boxes.

Do you have a "FN + something" key to increase the volume?

Usually when the volume button is pink(orangey) it means that the volume has been muted. Make sure both on the quick play bar right of the power button and in the task bar, that the volume has not been set to mute. Also check the audio drivers and make sure the drivers haven't been corrupt and reinstall or re-download new updated drivers in needed.

I'm not certain about yours, but my Acer Aspire 5920 has an audio/volume turn button, just under the lip of the laptop, just to the right of center. Even if you un-mute it, if the volume is turned down all the way - the button revolves, so looking a the front, turning it counter-clockwise will turn the volume down to off, and you won't hear a thing, no matter how much you try to un-mute the thing.
So turn that rotating button to the right, to make it louder, after you have un-muted a control panel volume slider and moved it up, and that just might make it work for you.
Good luck!

Yes, either flex cable(panel to motherboard) from control panel is bad or control panel itself.
Common problem.

Check the speaker icon in the taskbar at the bottom, if there is an X then it is muted. Right click to unmute.

Also as it is a laptop there may be a mute button on the keys using the function button and a typical mute icon on a key or even a seperate button altogether.

It sounds like you have muted your F20.
If this is the case you need to turn on the Sat Nav (outside so it picks up the Sats). Once the sats have loaded and machine is working. Press the arrow button bottom right, which takes you to map pages, press the screen on an empty area on the map page. This will bring up another on screen menu which gives you another 6 options (these include pausing routes, brightness etc..) one of the options is 'mute' (top right on screen button) press the button once and you should be un-muted.(It is one press to mute and press again to un-mute). Once un-muted, use the side + & - keys to raise and lower volume.
Hope this helps, if you are already un-muted and still have no volume, you may have a faulty unit. You could try a master reset by inserting a pin into the reset hole on the bottom of the unit.

Talk about silly. This is the 3rd time typing the solution. (The Terms of Use link wiped it out too.) I had same problem by accidentally setting mute from bluetooth headset. If you have same situation, just turn volume up or down on headset. (Turning volume up or down on cellphone did not help me.) Good Luck,
BeenThere