Nodes, undesired pixel/glitch effect Newbie here trying to make floor detailed tiles only using nodes. 

The problem is that a certain point I get this effect:



I refer to the squared glitches noticeable overall over the shine areas.

If I disconnect the node Color 2 property, this effect dissappears and all goes fine again:



IMPORTANT to know, this happens only when the Render Engine is EEVEE.
I'd like to continue rendering with Eevee while editing the nodes because is much faster, although in the final render probably I'll use Cycles.

So, what can be the reason of this problem I'm having? 
Thanks. 

Blend FILE:
I discovered that this is a known issue of Blender 2.81. Seems to happen when 4 or more 3d noise texture nodes are used. 

Bug details: https://developer.blender.org/T69776

With Blender 2.82 Beta works properly, at least in my case.