sACN viewer on nomad shows a "flicker" in output that doesn't show up on sACN traffic on the network

While troubleshooting something that seems to have been unrelated after all, I discovered that the sACN viewer within Eos is showing an irregular but frequent flicker.  Running 3.0.2 on a Macbook with Mojave, launched in Primary, recently unlocked to 12U output.  I can see this even if there's no real network there, or if the only other point is a second laptop running sACN viewer.  It's present via hardwire or wireless into the network, too.  The second laptop does NOT register a flicker if running a flickerfinder, and a Swisson on a node doesn't, either.  This is making sACN viewer useless as a diagnostic tool, though, and had me wasting a lot of time chasing something.  There's a similar thread from years ago of someone on 2.7 but I can't believe this issue is still real. What am I missing?

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