...for HD audio under the system devices in device manager? I'm trying to install the Realtek HD audio driver, but to no avail. Got some help that told me to "The offending agent appears to be the Microsoft UAA Bus Driver for High Definition Audio entry under the System Devices category in the Device Manager. It needs to be uninstalled before installing the realtek drivers. It won't uninstall unless you disable it first though. After disabling, then uninstalling, reboot and install the realtek driver."But I don't know how to do this.