Homekit camera is "offline" on my Mac but online on my iPhone

So here is yet another impossible thing to work out.

I have several HomeKit cameras that all work fine and show in the Home app on all my family member's iPhones.

Those same cameras appear to be offline in the Home app on my Mac, but the strange thing is, the preview window of the video does update with the real image every few seconds. Only when I click the preview, it shows the camera is offline. Jeez.

Restarted the Mac, cameras, routers... all devices are all up to date.

Go figure.