|The Gigabyte site shows 3 different versions of that model motherboard. Each one of them includes a Realtek sound chip. You may not have the correct drivers installed. |
First look at the motherboard circuit board for the version number. There is ver. 1, ver. 3 & ver. 3.1. Then go to the link below and download the correct drivers for your version of Windows.
I recommend you download and install ALL the drivers for your version and Windows version.
There is also a Manual download available, which should help you with the sound configuration.