you probably need to install the drivers from your motherboard for your sound.. unless your using a soundcard.. then you need to install the drivers for that..
cutting to the chase.. its a driving problem... give us your mobo model and i can try to help you out
Intel 3770k @ 4.4 GHZ | Galaxy GTX 770 SLi | 16 GB G.Skill Sniper | ASrock z77 Extreme4
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