I'm thinking of using a Stinger SGN12 Line Output Converter to to drop a pair of speaker level outputs from my HU (Clarion CMD6) to RCA level to feed the audio input of a RGB LED controller since all my HU RCA outputs will be feeding amps. The SGN12 has an "optional ground connection sometimes used to eliminate minor noise problems" according to the manual.

I have a dual battery setup with switch and VSR with one battery going to feed/ground only stereo components to help keep the noise down. The LED controller will be on the main battery & if I put the Stinger in line, it will be my only crossover point between the main and stereo circuits. I don't care about a little noise or sound quality of the signal going into the LED controller since it'll just be an amplitude signal, but...

Do you think the controller could feedback noise through its RCA level input, then the converter, then through the speaker level outputs of the HU, and then make its way to the HU RCA outputs connected to the amps? I'll probably try the converter ungrounded at first, but if I get noise going to the amps, should I connect the "optional" ground on the converter to the stereo or helm circuit? Thanks.