PAC Drive w/ 12V LED Buttons Problem (Dim lighting)

[Rantlers]

Hi, wondering if someone could guide me in the right direction.  I'm having an issue with the brightness of my 12V LED buttons, they're very dim when running LED Blinky.  The program recognizes all the buttons individually as expected, but I can't figure a way to increase the brightness (for the record they look incredibly bright when connecting +/- to a direct power source).  Things I've tried:

• 2A, 3A, and 5A 12V power supplies (only 14 buttons)
• Powered USB hub for the PAC Drive connection
• multiple different USB cables
• Connecting fewer buttons

The buttons: https://www.diyretroarcade.com/collections/arcade-parts-buttons/products/one-piece-design-28mm-led-12v-illuminated-buttons-switch-for-arcade1up-machines

Wiring setup: positive side daisy-chained directly to a 12V source and the ground wires connected to the individual terminals as recommended in the "Advanced Connection Methods" on Ultimarc's page.

[lilshawn]

your controller may be trying to drive the LED's on a floating ground... since the controller effectively switches the negative of your LED's to it's ground to "turn them on" ... you need to make sure your controller and your LED's power supply are sharing the same negative rail. you may have to tie one of the negative power leads from the power supply to the controller/computer ground or shield so they are switched to the same ground potential difference. (and not just the negative ground potential of the computer the controller is attached to.)

[Rantlers]

your controller may be trying to drive the LED's on a floating ground... since the controller effectively switches the negative of your LED's to it's ground to "turn them on" ... you need to make sure your controller and your LED's power supply are sharing the same negative rail. you may have to tie one of the negative power leads from the power supply to the controller/computer ground or shield so they are switched to the same ground potential difference. (and not just the negative ground potential of the computer the controller is attached to.)

You're incredible, thank you so much!  I simply touched a ground lead from the power supply to the USB terminal on the PAC Drive and the lights lit up like a Christmas tree.  Now just trying to figure out how to make a "cleaner" more permanent solution.