diff --git a/libraries/transformer/src/main/java/androidx/media3/transformer/MuxerWrapper.java b/libraries/transformer/src/main/java/androidx/media3/transformer/MuxerWrapper.java
index f46fa98db2..4150adafca 100644
--- a/libraries/transformer/src/main/java/androidx/media3/transformer/MuxerWrapper.java
+++ b/libraries/transformer/src/main/java/androidx/media3/transformer/MuxerWrapper.java
@@ -798,7 +798,7 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
      * there is no track data.
      */
     public int getAverageBitrate() {
-      if (timeUs <= 0 || bytesWritten <= 0) {
+      if (timeUs <= 0 || bytesWritten <= 0 || timeUs == startTimeUs) {
         return C.RATE_UNSET_INT;
       }