I'm not too sure but could you go to 'devices' under control panel and check if there are any updates for the sound drivers?
i have a problem of playing a sound on internet using apps like skype, and in chrome where i cannot hear sound on youtube or anyother sites (sometimes it plays the sound sometime not)
i have tried the audio mixer, played the test sound sometime it plays some time it says failed to test play so anyone can say whats the problem is and how can i resolve it

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