For turning the LEDs off, there is an "LED Refresh Mode" option in the Hardware menu. It has three options: Normal, Control Only, and All Off. Normal means the LEDs behave normally — Control Only means the keyboard lights turn off but the utility buttons on the left side stay on — All Off means all LEDs are off.
And similar to Danimal's solution, if people don't want to be running computers without ground they can get a USB isolator, which is basically just a ground lift for a USB signal. Put it between the computer and QuNexus and the noise goes away.
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