It does appear that you posted issues earlier this year and noted this same motherboard. Can you say the audio was fine then? You didn't mention the OS but I know this can happen a default speaker device is assigned to a different port. Speaker ports (RCA mini jack) can find themselves mute if the default output is to such as USB headphones.
I cannot get audio from either my front or back audio jack. I have uninstalled and reinstalled the soundtek drivers from the Asus CD that came with the mother board. If I play a song, the meters show that music is playing but I'm not getting anything from the jacks. I have tested the audio cable by plugging it into a smart phone that was playing music and it worked so I know the cable is good.

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