Does anyone have any experience with RGB LED strip/ribbon lights? I have a curious case of a lighting controller that's designed to work with these types of lights but seems to be implemented completely incorrectly.

The lights are the variety that come on a reel and are often sold in a kit with a 12v power supply and a remote-controlled RGB controller to change colors and turn the strip on and off. The controller I'm having the issue with is a separate product that provides some of the same features but can also automatically change the lighting in reaction to sound.

The light strip has 4 wires, RGB and a BLACK wire. Going by the functionality of the working controller and manual connection to a power supply, the black wire is a common ground and each of the R,G and B wires are supplied with varying voltage (+12 to 0) which determines the intensity of each light component and creates the varying colors.

The issue with the music/sound controller is that it doesn't have a common ground. It has common voltage, and each terminal for RG and B are then tied to ground, first passing through some bits on the circuit board (1 transistor each, plus some resistors, then tied to a small IC) to reduce the voltage on input from the remote. This means that the voltage is passing in reverse polarity through the LED strip, -12v instead of +12v. And of course the LED strip will not light up this way.

Which leaves me with a giant WTF!?

Reversing polarity on the power supply doesn't work to remedy the problem - no voltage can be measured on the board this way. Might this be a matter of flipping around a few components to get this to work? I only see 3 diodes on the entire board, one big through-hole and two smt.

I purchased this stuff from two sellers on Amazon, but I notice that the seller I bought the strip from also has the exact same controller on their web site. Arrgh.