diff --git a/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/tags/Tag.java b/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/tags/Tag.java
index 220d4358d..e353f7a48 100644
--- a/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/tags/Tag.java
+++ b/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/tags/Tag.java
@@ -459,12 +459,12 @@ public abstract class Tag implements NeedsCharacters, Exportable, Serializable {
         return originalRange != null && isModified();
     }
 
-    public void undo() throws InterruptedException, IOException {
-        byte[] data = getOriginalData();
-        if (data == null) { //If the tag is newly created in GUI it has no original data
+    public void undo() throws InterruptedException, IOException {        
+        if (originalRange == null) { //If the tag is newly created in GUI it has no original data
             return;
         }
-        SWFInputStream tagDataStream = new SWFInputStream(swf, data, getDataPos(), data.length);
+        SWFInputStream tagDataStream = new SWFInputStream(swf, originalRange.getArray(), 0, (int) originalRange.getPos() + originalRange.getLength());
+        tagDataStream.seek(getDataPos());
         readData(tagDataStream, getOriginalRange(), 0, false, true, false);
         setModified(false);
     }