Hum created on my eurorack

There is a hum generated on my eurorack when I enter automation steps for the modulation envelope, but only when I’m in step editing mode. The hum is there as soon as I draw the automation curve for the envelope. If I turn individual steps off, the hum gets quieter until with no steps it disappears. It also disappears completely if I simply leave step mode (with the automation remaining). Weird. Anyone else experience this?

OK switching to PSU rather than powering from my desktop PC fixed this:)
Must have been a grounding thing

I have experienced this buzzing as well when using the PSU supplied by Squarp.
I figured it was because I am in the US where the power sockets are 110V (vs 220V in Europe)

I plug my Pyramid into a USB powered battery and that seems to supply the right level of power.

I had similar issues when powering Pyramid from PSUs. I now power it from a Doepfer A-183-9 Quad USB Supply, and all issues (including hums) are gone.