on trying to hear You Tube videos the speaker appears to be on mute and there is no sound. I haven't set to mute at all. Running Win 8 and on the settings charm volume is showing as 78%. I can increase/decrease this % by using Fn key + F11 or F12 key (that is just the % - still have no actual volume). So I thought I would be able to turn off the mute by using Fn key + F10 but this has no effect. Clicking on the muted speaker within You tube also has no effect. Is there somewhere simple to control mute on/off from?