diff --git a/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/V2/FullDataSourceProviderV2.java b/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/V2/FullDataSourceProviderV2.java
index 5c2207212..32dad829b 100644
--- a/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/V2/FullDataSourceProviderV2.java
+++ b/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/V2/FullDataSourceProviderV2.java
@@ -134,14 +134,14 @@ public class FullDataSourceProviderV2 implements IDebugRenderable, AutoCloseable
 	
 	public void addDataSourceUpdateListener(IDataSourceUpdateListenerFunc<FullDataSourceV2> listener)
 	{
-		synchronized (this.dataUpdater)
+		synchronized (this.dataUpdater.dateSourceUpdateListeners)
 		{
 			this.dataUpdater.dateSourceUpdateListeners.add(listener);
 		}
 	}
 	public void removeDataSourceUpdateListener(IDataSourceUpdateListenerFunc<FullDataSourceV2> listener)
 	{
-		synchronized (this.dataUpdater)
+		synchronized (this.dataUpdater.dateSourceUpdateListeners)
 		{
 			this.dataUpdater.dateSourceUpdateListeners.add(listener);
 		}
diff --git a/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/V2/FullDataUpdaterV2.java b/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/V2/FullDataUpdaterV2.java
index e9d2d9790..d82f707bf 100644
--- a/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/V2/FullDataUpdaterV2.java
+++ b/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/V2/FullDataUpdaterV2.java
@@ -150,11 +150,14 @@ public class FullDataUpdaterV2 implements IDebugRenderable, AutoCloseable
 						}
 						
 						
-						for (IDataSourceUpdateListenerFunc<FullDataSourceV2> listener : this.dateSourceUpdateListeners)
+						synchronized (this.dateSourceUpdateListeners)
 						{
-							if (listener != null)
+							for (IDataSourceUpdateListenerFunc<FullDataSourceV2> listener : this.dateSourceUpdateListeners)
 							{
-								listener.OnDataSourceUpdated(recipientDataSource);
+								if (listener != null)
+								{
+									listener.OnDataSourceUpdated(recipientDataSource);
+								}
 							}
 						}
 					}