Do you have the latest BIOS update on your mainboard? The latest version is 1.9
You can find it here
Also please make sure that you have the latest Windows update, please also click the Check Windows update online under the Windows update window once updates has been checked or completed. It will normally find more updates
Are you overclocking your system? If you are, please check if by placing the mainboard default BIOS settings you experience the same results.
Please try to give more information of your system such as the OS, I found that the latest on board audio drivers is from May 14th. Also make sure that you also have the latest system and Chipset drivers