diff --git a/libraries/transformer/src/main/java/androidx/media3/transformer/TransformerInternal.java b/libraries/transformer/src/main/java/androidx/media3/transformer/TransformerInternal.java
index 005581944d..4f4078334b 100644
--- a/libraries/transformer/src/main/java/androidx/media3/transformer/TransformerInternal.java
+++ b/libraries/transformer/src/main/java/androidx/media3/transformer/TransformerInternal.java
@@ -377,9 +377,9 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
     private final MediaItem mediaItem;
     private final FallbackListener fallbackListener;
 
-    private long durationUs;
     private int tracksAddedCount;
 
+    private volatile long durationUs;
     private volatile boolean trackRegistered;
 
     public ComponentListener(MediaItem mediaItem, FallbackListener fallbackListener) {