No sounds from speakers, headphones @SuperMario1 : Audio does not work

@SuperMario1 : Troublesho​oting Guide: Audio does not Work after a Certain Period of Time.

Hi All,

I hav bought HP Pavillion Windows 8 in Septmeber 2013. 

From past two days, I am getting problem related to sounds. No sound is coming from speakers or head phones connected. No Mute sign is there, I checked for it. Although, in Keyboard, the light of Sound button should change after pressing it, but it's not changing. However on clicking that button, it is displayed on screen that the laptop is muted or un-muted.

I am not able to diagnosis the problem within the system.

Please help. 

Thanks in advance.

Note: I did not updated the latests Windows 8 version.