diff --git a/src/com/jpexs/decompiler/flash/gui/ImagePanel.java b/src/com/jpexs/decompiler/flash/gui/ImagePanel.java
index 8487eca21..e9db598e4 100644
--- a/src/com/jpexs/decompiler/flash/gui/ImagePanel.java
+++ b/src/com/jpexs/decompiler/flash/gui/ImagePanel.java
@@ -2515,8 +2515,10 @@ public final class ImagePanel extends JPanel implements MediaDisplay {
                 }
             }
         };
-        if (timer != null) {
-            timer.schedule(task, msDelay);
+        synchronized (ImagePanel.this) {
+            if (timer != null) {
+                timer.schedule(task, msDelay);
+            }
         }
     }