In reading your issue, it shares a number of traits with mine, which I am referencing here: Similar Issue.
In my case, I am running the core on a powerful NAS and there is no performance/capacity problem on the core hardware - however I see the same issues, momentary loss of output zones, etc. I too note that the problem is more frequent since 1.6. I note other references to similar problems throughout these boards. I suspect there is some common underlying cause which is being obfuscated as these are all treated individually as networking / configuration issues in support versus escalating and approaching this as a core bug.