Ground Loop Noise

[Iamthejazz123]

I built a box that only splits a stereo signal into 2 mono signals. My problem is that I'm getting ground loop buzz from the splitter (not RF noise). I don't get the noise when I use an off-the-shelf Hosa brand splitter cable even though the rest of the cables I'm using are the same. I've isolated it to the splitter itself. Any ideas as to why? It's a powder coated aluminum enclosure. I just wired the tip of the stereo jack to the tip of one mono jack, the ring of the stereo jack to the tip of the other mono jack, and both mono grounds are connected to the stereo jack ground. I wrapped the jacks in electrical tape, so nothing is touching the box itself.

[Markw5]

Maybe the problem is that the case is floating from ground. What if you connect it to ground (sleeve) on one of the connectors?

[GibsonGM]

If it's all in a metal enclosure, ground ONE of the jacks (allow it to touch the box, what Mark there is getting at).   Does that help?