i had the same error, i found what was happening.
if a player puts a redstone torch over the wall, a jacketed wire above the redstone torch and a "Talisman of Repair" item above the jacketed wire, the console starts spamming and the server becomes unplayable.
i wish i would know how to program a java plugin that prevents you from placing talisman of repair next to jacketed wire.....
i will see what i can do for it. for now i will just disable the talisman of repair