The integration between Indigo Pro, my “regular” automation controller, and Home Assistant broke. So I connected the Insteon interface (a PowerLinc Modem, dual mesh) to Home Assistant and this quirk that I had observed other times I tried this before returned: whenever Home Assistant is in charge of Insteon, lights flicker. It is as if they were non-dimmable solid state types that don’t have enough power just yet to fully turn on. It may be the perception caused by the flicker but it seems they don’t ramp all the way up stopping somewhere around ninetyish percent.
On the upside, the issues where devices didn’t respond or did repond but then flipped back seem gone for good though, and I wonder if Home Assistant’s polling or whatsitcalled the Insteon network to make sure devices responded which is causing the flickering. I have confirmed it comes from Home Assistant, though: when I unplug the interface from Home Assistant (not even to the hypervisor, just remove it in software leaving it physically plugged in) the flickering stops.
Back on the (macOS-only) Indigo side, way back, WAAAY back, it was that time of the year when Apple broke things for everyone, among those was the connection to the PowerLinc Modem that time. The Indigo team discovered this could be fixed by simply putting a (bus-powered) USB hub between the Mac and the PLM, and since then that’s been the norm.
I believe it was related to kexts (drivers) somehow, IDK. I don’t think it was ever explained how could a hub helped. Could it perhaps help in this case too?. TBH, I have rather strong reservations about this because of the abstraction layers virtualization might already putting in place. That, and it’s flickered before on past installations running bare-metal, running as a Fusion VM (with obviously macOS controlling access to USB), as a macOS privileged container (Docker & Nautilus), as a Linux privileged container (Docker & Moby), and as it is now; on vSphere (VMware’s type 1 hypervisor). But still…I’m hopeful.
I guess it couldn’t hurt testing that in the meantime. But I hope there’s some real fix for this, maybe a timing that wasn’t adjusted, lowering the USB spec to 1.1, something… 
