Here are my observations from the beta driver:
1) I Installed the beta driver (after uninstalling the previous one first) and it didn't install the control panel "SupremeFX". So, there was no way I could check whether the Amplification level setting was retained after rebooting, because there was no way I could even see the setting itself. The app/control panel that exposes the setting was not even installed.
2) Then I reformatted, reinstalled Windows, and installed the beta driver version 8318, and same result as #1 above was obtained.
3) Then I installed the older driver (version 8219) on top of the beta one you linked (version 8318), and the SupremeFX control panel app was available again, and it did retain the setting after rebooting when I set the Amplification level to "Performace” (and again, as per my OP, there's a typo here, "Performace" should read "Performance"). Relying on my knowledge of how Windows works, I assume installing the older driver installed the SupremeFX control panel as it should, but Windows did not let it overwrite the newer driver files from beta driver v8318, so the new beta driver worked as it should once it was provided with the missing files for a working SupremeFX control panel.
4) When switching my speaker configuration to "5.1 surround" from the default "Stereo", I had no sound from the center and sub channels. I rebooted, and this was resolved, but instead I had no sound from the rear channel. I had to unplug and re-plug the audio jacks and reboot for all speakers to work as expected.
5) After switching to 5.1 Surround mode for my speakers, I also found that the setting did not appear to apply to the front speaker’s channel: The front speakers outputted a much louder volume than the rear/center/sub channels.
6) Installing the other way around, meaning the older driver first (8219), then the beta driver (8318), leaves me without the SupremeFX control panel. Furthermore, it leaves me without speakers. What I mean by this is without the SupremeFX control panel, the only audio driver-related settings I have access to is through the Windows built-in settings themselves i.e. right-click the speaker/volume icon on the system tray, and choose "Playback Devices". When doing this, "Playback Devices" lists all playback devices for my system, but "Speakers" device is missing, leaving me with only the other devices that I don’t typically use.
Martin
EDIT: I'll do further testing. Reformatting again and reinstalling drivers to confirm some of the above observations, and hopefully gather more information (I forgot to monitor what has happening in the registry, etc...)
