diff --git a/RELEASENOTES.md b/RELEASENOTES.md
index 21bfce104b..96d315ca65 100644
--- a/RELEASENOTES.md
+++ b/RELEASENOTES.md
@@ -89,6 +89,9 @@
         instead.
     *   Remove `Transformer.startTransformation(MediaItem,
         ParcelFileDescriptor)`.
+    *   Fix a bug where transformation could get stuck (leading to muxer
+        timeout) if the end of the video stream was signaled at the moment when
+        an input frame was pending processing.
 *   DASH:
     *   Fix handling of empty segment timelines
         ([#11014](https://github.com/google/ExoPlayer/issues/11014)).
diff --git a/libraries/effect/src/main/java/androidx/media3/effect/ExternalTextureManager.java b/libraries/effect/src/main/java/androidx/media3/effect/ExternalTextureManager.java
index 359e15f5cf..1957d073fa 100644
--- a/libraries/effect/src/main/java/androidx/media3/effect/ExternalTextureManager.java
+++ b/libraries/effect/src/main/java/androidx/media3/effect/ExternalTextureManager.java
@@ -56,6 +56,12 @@ import java.util.concurrent.atomic.AtomicInteger;
 
   // Read and written on the GL thread only.
   private boolean inputStreamEnded;
+
+  // TODO(b/278273122): Remove this flag and the signal end of input call after queueing a frame if
+  // all frames notify that they've been processed.
+
+  // Read and written on the GL thread only.
+  private boolean hasSignaledEndOfInput;
   // The frame that is sent downstream and is not done processing yet.
   // Set to null on any thread. Read and set to non-null on the GL thread only.
   @Nullable private volatile FrameInfo currentFrame;
@@ -128,7 +134,11 @@ import java.util.concurrent.atomic.AtomicInteger;
     videoFrameProcessingTaskExecutor.submit(
         () -> {
           currentFrame = null;
-          maybeQueueFrameToExternalShaderProgram();
+          if (inputStreamEnded && pendingFrames.isEmpty()) {
+            maybeSignalEndOfInput();
+          } else {
+            maybeQueueFrameToExternalShaderProgram();
+          }
         });
   }
 
@@ -173,7 +183,7 @@ import java.util.concurrent.atomic.AtomicInteger;
         () -> {
           inputStreamEnded = true;
           if (pendingFrames.isEmpty() && currentFrame == null) {
-            externalShaderProgram.signalEndOfCurrentInputStream();
+            maybeSignalEndOfInput();
           }
         });
   }
@@ -235,6 +245,13 @@ import java.util.concurrent.atomic.AtomicInteger;
     checkStateNotNull(pendingFrames.remove());
 
     if (inputStreamEnded && pendingFrames.isEmpty()) {
+      maybeSignalEndOfInput();
+    }
+  }
+
+  private void maybeSignalEndOfInput() {
+    if (!hasSignaledEndOfInput) {
+      hasSignaledEndOfInput = true;
       externalShaderProgram.signalEndOfCurrentInputStream();
     }
   }