You are posting in the Vista/Windows 7 forum, but your profile says you are running Windows XP SP2?
The Policy is set on the OS you are in. You cannot set a policy from a Windows cloned image. But you can restore your OS from your cloned image. You will loose all files that have been installed since, so backup your files first. Restoring a cloned image will reset the policy.
You do not need to change the policy to change drivers, Go to the Device Manager, right click your Audio device and choose Uninstall. It will ask if you want to uninstall the driver files as well, click Yes. After a restart, install the Realtek driver you want.
The Policy is set on the OS you are in. You cannot set a policy from a Windows cloned image. But you can restore your OS from your cloned image. You will loose all files that have been installed since, so backup your files first. Restoring a cloned image will reset the policy.
You do not need to change the policy to change drivers, Go to the Device Manager, right click your Audio device and choose Uninstall. It will ask if you want to uninstall the driver files as well, click Yes. After a restart, install the Realtek driver you want.