I am having the same problem on our server (Direwolf20 1.10 [1.14 Stable]) which has IC2 2.6.105-ex110. I reviewed the change logs and did not see this issue addressed in the updates since this version. I can right click the invisible block (batbox for example) with the debug item and get output:
Code
te: ic3.core.block.wiring.TileEntityElectricBatBox@19874dc2
[mp server] interfaces: ic2.core.IHasGui
ic2.api.network.INetworkClientTileEntityEventListener
ic2.api.tile.IEnergyStorage
net.minecraft.inventory.ISidedInventory
ic2.api.network.INetworkDataProvider
ic2.api.network.INetworkUpdateListener
net.minecraft.util.ITickable
ic2.core.gui.dynamic.IGUIConditionProvider
net.minecraftforge.common.capabilities.ICapabilitySerializableThe same symptoms happened to the macerator and gold 2x cable our user attached to the machine. Appreciate the support, let me know if I can help further.