diff --git a/src/main/java/com/raoulvdberge/refinedstorage/tile/TileController.java b/src/main/java/com/raoulvdberge/refinedstorage/tile/TileController.java
index e4a8640c3..d92528100 100755
--- a/src/main/java/com/raoulvdberge/refinedstorage/tile/TileController.java
+++ b/src/main/java/com/raoulvdberge/refinedstorage/tile/TileController.java
@@ -528,13 +528,17 @@ public class TileController extends TileBase implements INetworkMaster, IEnergyR
                 remainder = storage.insertItem(remainder, size, simulate);
             }
 
-            if (storage instanceof ItemStorageExternal && !simulate) {
-                ((ItemStorageExternal) storage).updateCacheForcefully();
-            }
-
             if (remainder == null || remainder.stackSize < 0) {
+                if (storage instanceof ItemStorageExternal && !simulate) {
+                    ((ItemStorageExternal) storage).updateCacheForcefully();
+                }
+
                 break;
             } else {
+                if (size != remainder.stackSize && storage instanceof ItemStorageExternal && !simulate) {
+                    ((ItemStorageExternal) storage).updateCacheForcefully();
+                }
+
                 size = remainder.stackSize;
             }
         }
diff --git a/src/main/java/com/raoulvdberge/refinedstorage/tile/externalstorage/ItemStorageExternal.java b/src/main/java/com/raoulvdberge/refinedstorage/tile/externalstorage/ItemStorageExternal.java
index 94d125dfa..163677693 100755
--- a/src/main/java/com/raoulvdberge/refinedstorage/tile/externalstorage/ItemStorageExternal.java
+++ b/src/main/java/com/raoulvdberge/refinedstorage/tile/externalstorage/ItemStorageExternal.java
@@ -14,16 +14,16 @@ public abstract class ItemStorageExternal implements IItemStorage {
     public boolean updateCache() {
         List<ItemStack> items = getStacks();
 
-        if (cache == null) {
-            cache = items;
+        if (this.cache == null) {
+            this.cache = items;
         } else if (items.size() != cache.size()) {
-            cache = items;
+            this.cache = items;
 
             return true;
         } else {
             for (int i = 0; i < items.size(); ++i) {
                 if (!API.instance().getComparer().isEqual(items.get(i), cache.get(i))) {
-                    cache = items;
+                    this.cache = items;
 
                     return true;
                 }
@@ -34,6 +34,6 @@ public abstract class ItemStorageExternal implements IItemStorage {
     }
 
     public void updateCacheForcefully() {
-        cache = getStacks();
+        this.cache = getStacks();
     }
 }