Not 100% sure if this is a bug, a possibility for a feature, or not possible at all:
System Volume %'s do not function when Volume Normalization is Enabled. The Volume Normalization feature is greatly appreciated to balance out different base volumes of arcade games, but the ability to adjust/limit volume when enabled, outside of a physical volume knob of speakers or TV volume controls, is currently not possible/functioning. If this is a bug, a remedy would be greatly appreciated. If this is a feature request, this would be very helpful to have control via the interface, especially when using headphones. Thank you for all your hard work!