Need to restart my laptop every time to get sound.

Hi ,
I got a problem with Sound in Windows 8 Operating System (hP G60 model)..Device drivers are installed properly ..!! I need to restart my laptop every time problem occurs..if i restart the laptop, sound is working fine..!!..I have no idea why its not coming sound when i first switch on laptop.!every time i need to restart laptop for sound.! one more problem is if i haven't used laptop for 15-20min it goes sleeping mode and when i used back - again facing same problem.!!..Does i need to install any drivers?..Does it require?..Plz help me out..Thank your for your help in advance.!!