In dedicated server, some actions, like place a tool in your hand, multiple craftings, grab something dropped, cause the server to kick you, with these errors: 08.02 23:25:57 [Server] INFO Caused by: java.lang.IllegalArgumentException: value already present: (7,com.gildedgames.aether.common.entities.effects.InventoryProvider@cc43c07a) or... 08.02 23:25:57 [Server] Server thread/ERROR [FML]: 1: ASM: class com.gildedgames.aether.common.capabilities.entity.player.PlayerAetherHooks onPlayerTick(Lnet/minecraftforge/fml/common/gameevent/TickEvent$PlayerTickEvent;)V 08.02 23:25:57 [Server] Server thread/ERROR [FML]: 0: NORMAL 08.02 23:25:57 [Server] Server thread/ERROR [FML]: Index: 1 Listeners: or... 08.02 23:25:57 [Server] Server thread/ERROR [FML]: Exception caught during firing event net.minecraftforge.fml.common.gameevent.TickEvent$PlayerTickEvent@49bfc428: 08.02 23:25:57 [Server] INFO java.lang.IllegalArgumentException: value already present: (7,com.gildedgames.aether.common.entities.effects.InventoryProvider@cc43c07a)

Some Users in NODATS (My Aether II Server) also experience the same crash, no idea how or why, but it results in the same stacktrace

I got the same crash from standing around on the server. However, doing the other stuff doesn't seem to cause me to crash.