Your situation here is very familiar to me. Let me just explain how I went about solving it.
I bought a bunch of Eastwick Modular Alpha cases. 2 6U Alphas and 2 3U Alphas. I was using 4ms Row powers daisy chained with flying bus cables.
As I was building up my rack things were great until I all of a sudden got the Morpheus, Control Forge, and a 1010 Synthbox and Toolbox. All of a sudden I had noise. It was a lot too.
I wrote countless posted about it on Muffs, and tried really hard to wrap my head around power and my problems. I spent many many hours, days, and weeks on it.
Around this time the LIBB module from Genus Modu was coming out, and I thought, this has has to be my solution. I tried everything else. (I even bought a ground loop isolator both in eurorack and external formats) So I got them and installed them. Took forever, and I had to drill holes in my Alphas. No sweat, I never look at the backs.
Plugged everything back in, and turned it all back on and guess what… the noise was STILL there. Granted it was MUCH MUCH lower, but it was still there.
Finally I just decided to buy a new power brick. I got 2 meanwell 60w power bricks. I plugged them in, thinking it wasn’t going to do anything, BUT much to my surprise, my noise had completely dissappeared. Gone completely.
Now I don’t know if all I needed was really just another power brick, but I guess what I’m trying to get at is that power is complicated. Digital modules are in many ways the new kids on the block, and most power solutions don’t really account for them very well.
A board like the LIBB and qaulity power cables go along way, but even they wont stop noise from a crappy power brick.
My crappy power brick? The 4ms 90 watt brick.
Anyway, I hope you get your power problems resolved. Mine about drove me up the wall, so you have my sympathies!