Is there a way to lock the internal audio on a 7040 to a certain percentage where it can not be turned off or down? I have cash registers where I need cashiers to hear audio prompts and they either mute or turn down audio in windows? I have hidden speakers in the taskbar but they find workarounds. From Dell these came to where the audio automatically goes to 67% volume at reboot. I want to lock them at about 40% and have it so the audio level can not be messed with in windows...