Make sure you have'nt muted it by means of a hotkey on your notebook. If you have'nt go to Start>Run, then type 'dxdiag' and hit enter, this will run a sound and video diagnostic driver test. See what it says after running it, it may be you need to re install drivers for sound, if so go to this site and download. http://h10025.www1.hp.com/ewfrf/wc/softwareList?os=228&lc=en&cc=us&lang=en&product=95526&dlc=en
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