Audible digital chatter when Nucleus One connected to HDMI?

I just bought a Nucleus One. I installed a Samsung SSD, migrated my DB and my music library with no problems and installed it in the cabinet next to my Anthem MRX-1140 receiver with an Apple TV+ and Ubiquity Flex-Mini stacked on top. It fits perfectly.

Unfortunately, when I connect it to the receiver (which is off) via HDMI, my subwoofer (which is on the shelf below the amplifier and the Nucleus) suddenly comes to life, putting out low-frequency digital chatter; I’m sure you know what i mean: pop, pop…whirrrrrrrrrr…pop…whirr…whirr…pop, etc.

My presumption is that this is being induced through the subwoofer cable. I completely rearranged the space so that the speaker cables and the incoming HDMI cables were as far from one another as they could be, considering that they’re plugged into the same receiver—same issue. I tried a heftier (and presumably better shielded?) HDMI cable, no change.

I will admit that I haven’t yet tried unplugging the subwoofer cable from the receiver; I have a shorter cable on order (the installers used a multi-meter cable for an 18" run and just coiled the rest, which could make it more of an antenna), and will experiment then.

But mostly I wanted to see if anyone else had run into this problem?

(If Anthem would actually get their Roon support deployed–never by equipment based on what they way will happen in the future–I absolutely wouldn’t care, but this HDMI connection is potentially my highest fidelity option right now).

Thanks, Mike.

Ambiguous sound descriptions notwithstanding, this might be similar to:

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It sounds like a groundplane loop. The signal ground should only be connected to mains earth at one point, usually through the power amp. With a ground loop noise from the computer can walk around in loops because some other device has the ground also connected to mains earth. It can happen when some galvanic isolator is overruled like when going from usb (isolated at the dac) to spdif (no isolation).
What you could try is disconnection the earth at one of the suspicious devices and hear if the noise stops. If you are not sure about electricity then have your installer do this trick.
There are some devices that cut the ground at the signal level, like the iDefender but I don’t know about hdmi.

I refer to the sounds as described above (Suedkiez).
Have you tried to place the ac adapter as far away as possible from the subwoofer (-wires)?
The ac adapter can send noise that is picked up by the subwoofer amp (I assume it is a powered sub).

It sounds like the noise you’d get from a mechanical hard drive. Do you have a spinner hooked up somewhere?