Sorry you're having troubles with the plates. I swear I have this exact problem with my Ground Control plates, but they are the Race style, not street, and I'm on an Eibach race spring (2.25"). I expect some noise, but what I'm hearing doesn't sound right. It's like the noise you describe OP and it comes from the top mount area. I'm starting to think they are defective because I've checked everything else there is to check.
Also, my noise will at times completely go away. it's the strangest thing. It definitely acts up more in cold weather, but in warmer weather it's still there, just not as bad. During my track events, I've never ever heard or felt anything weird going on so I literally have no clue what the problem is, and I've pretty much given up trying to figure it out
the plates/dampers/springs were also installed at a shop that is
heavily involved in the BMW club racing scene, so I trust they know their way around a camber plate