diff --git a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/analytics/DefaultAnalyticsCollector.java b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/analytics/DefaultAnalyticsCollector.java
index adbb659ff4..8b3bee79f3 100644
--- a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/analytics/DefaultAnalyticsCollector.java
+++ b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/analytics/DefaultAnalyticsCollector.java
@@ -409,7 +409,7 @@ public class DefaultAnalyticsCollector implements AnalyticsCollector {
     EventTime eventTime = generateMediaPeriodEventTime(windowIndex, mediaPeriodId);
     sendEvent(
         eventTime,
-        C.INDEX_UNSET,
+        /* eventFlag= */ C.INDEX_UNSET,
         listener -> listener.onLoadStarted(eventTime, loadEventInfo, mediaLoadData));
     sendEvent(
         eventTime,
diff --git a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/MediaSourceEventListener.java b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/MediaSourceEventListener.java
index 3a427f98f8..d61cabc12f 100644
--- a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/MediaSourceEventListener.java
+++ b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/MediaSourceEventListener.java
@@ -234,7 +234,7 @@ public interface MediaSourceEventListener {
           /* trackSelectionData= */ null,
           /* mediaStartTimeUs= */ C.TIME_UNSET,
           /* mediaEndTimeUs= */ C.TIME_UNSET,
-          /* retryCount= */ retryCount);
+          retryCount);
     }
 
     /** Dispatches {@link #onLoadStarted(int, MediaPeriodId, LoadEventInfo, MediaLoadData, int)}. */
diff --git a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/ProgressiveMediaPeriod.java b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/ProgressiveMediaPeriod.java
index b523d2f4f0..a8954050d7 100644
--- a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/ProgressiveMediaPeriod.java
+++ b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/ProgressiveMediaPeriod.java
@@ -600,28 +600,26 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
   @Override
   public void onLoadStarted(
       ExtractingLoadable loadable, long elapsedRealtimeMs, long loadDurationMs, int retryCount) {
-    if (retryCount > 0) {
-      StatsDataSource dataSource = loadable.dataSource;
-      LoadEventInfo loadEventInfo =
-          new LoadEventInfo(
-              loadable.loadTaskId,
-              loadable.dataSpec,
-              dataSource.getLastOpenedUri(),
-              dataSource.getLastResponseHeaders(),
-              elapsedRealtimeMs,
-              loadDurationMs,
-              dataSource.getBytesRead());
-      mediaSourceEventDispatcher.loadStarted(
-          loadEventInfo,
-          C.DATA_TYPE_MEDIA,
-          C.TRACK_TYPE_UNKNOWN,
-          /* trackFormat= */ null,
-          C.SELECTION_REASON_UNKNOWN,
-          /* trackSelectionData= */ null,
-          /* mediaStartTimeUs= */ loadable.seekTimeUs,
-          durationUs,
-          retryCount);
-    }
+    StatsDataSource dataSource = loadable.dataSource;
+    LoadEventInfo loadEventInfo =
+        new LoadEventInfo(
+            loadable.loadTaskId,
+            loadable.dataSpec,
+            dataSource.getLastOpenedUri(),
+            dataSource.getLastResponseHeaders(),
+            elapsedRealtimeMs,
+            loadDurationMs,
+            /* bytesLoaded= */ 0);
+    mediaSourceEventDispatcher.loadStarted(
+        loadEventInfo,
+        C.DATA_TYPE_MEDIA,
+        C.TRACK_TYPE_UNKNOWN,
+        /* trackFormat= */ null,
+        C.SELECTION_REASON_UNKNOWN,
+        /* trackSelectionData= */ null,
+        /* mediaStartTimeUs= */ loadable.seekTimeUs,
+        durationUs,
+        retryCount);
   }
 
   @Override
@@ -908,20 +906,8 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
       pendingResetPositionUs = C.TIME_UNSET;
     }
     extractedSamplesCountAtStartOfLoad = getExtractedSamplesCount();
-    long elapsedRealtimeMs =
-        loader.startLoading(
-            loadable, this, loadErrorHandlingPolicy.getMinimumLoadableRetryCount(dataType));
-    DataSpec dataSpec = loadable.dataSpec;
-    mediaSourceEventDispatcher.loadStarted(
-        new LoadEventInfo(loadable.loadTaskId, dataSpec, elapsedRealtimeMs),
-        C.DATA_TYPE_MEDIA,
-        C.TRACK_TYPE_UNKNOWN,
-        /* trackFormat= */ null,
-        C.SELECTION_REASON_UNKNOWN,
-        /* trackSelectionData= */ null,
-        /* mediaStartTimeUs= */ loadable.seekTimeUs,
-        durationUs,
-        /* retryCount= */ 0);
+    loader.startLoading(
+        loadable, this, loadErrorHandlingPolicy.getMinimumLoadableRetryCount(dataType));
   }
 
   /**
diff --git a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/SingleSampleMediaPeriod.java b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/SingleSampleMediaPeriod.java
index c7da1aadfd..79e7b7151e 100644
--- a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/SingleSampleMediaPeriod.java
+++ b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/SingleSampleMediaPeriod.java
@@ -155,21 +155,10 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
       dataSource.addTransferListener(transferListener);
     }
     SourceLoadable loadable = new SourceLoadable(dataSpec, dataSource);
-    long elapsedRealtimeMs =
-        loader.startLoading(
-            loadable,
-            /* callback= */ this,
-            loadErrorHandlingPolicy.getMinimumLoadableRetryCount(C.DATA_TYPE_MEDIA));
-    eventDispatcher.loadStarted(
-        new LoadEventInfo(loadable.loadTaskId, dataSpec, elapsedRealtimeMs),
-        C.DATA_TYPE_MEDIA,
-        C.TRACK_TYPE_UNKNOWN,
-        format,
-        C.SELECTION_REASON_UNKNOWN,
-        /* trackSelectionData= */ null,
-        /* mediaStartTimeUs= */ 0,
-        durationUs,
-        /* retryCount= */ 0);
+    loader.startLoading(
+        loadable,
+        /* callback= */ this,
+        loadErrorHandlingPolicy.getMinimumLoadableRetryCount(C.DATA_TYPE_MEDIA));
     return true;
   }
 
@@ -220,7 +209,7 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
             dataSource.getLastResponseHeaders(),
             elapsedRealtimeMs,
             loadDurationMs,
-            sampleSize);
+            /* bytesLoaded= */ 0);
     eventDispatcher.loadStarted(
         loadEventInfo,
         C.DATA_TYPE_MEDIA,
diff --git a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/ads/ServerSideAdInsertionMediaSource.java b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/ads/ServerSideAdInsertionMediaSource.java
index 2b1c569ec1..1b1d96b2f6 100644
--- a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/ads/ServerSideAdInsertionMediaSource.java
+++ b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/ads/ServerSideAdInsertionMediaSource.java
@@ -431,14 +431,14 @@ public final class ServerSideAdInsertionMediaSource extends BaseMediaSource
       int retryCount) {
     // TODO file a bug to track updating this.
     if (retryCount == 0) {
-    @Nullable
-    MediaPeriodImpl mediaPeriod =
-        getMediaPeriodForEvent(mediaPeriodId, mediaLoadData, /* useLoadingPeriod= */ true);
-    if (mediaPeriod == null) {
+      @Nullable
+      MediaPeriodImpl mediaPeriod =
+          getMediaPeriodForEvent(mediaPeriodId, mediaLoadData, /* useLoadingPeriod= */ true);
+      if (mediaPeriod == null) {
         mediaSourceEventDispatcherWithoutId.loadStarted(
             loadEventInfo, mediaLoadData, /* retryCount= */ 0);
-    } else {
-      mediaPeriod.sharedPeriod.onLoadStarted(loadEventInfo, mediaLoadData);
+      } else {
+        mediaPeriod.sharedPeriod.onLoadStarted(loadEventInfo, mediaLoadData);
         mediaPeriod.mediaSourceEventDispatcher.loadStarted(
             loadEventInfo,
             correctMediaLoadData(
diff --git a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/chunk/ChunkSampleStream.java b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/chunk/ChunkSampleStream.java
index 0ba48bce0e..6c897a91df 100644
--- a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/chunk/ChunkSampleStream.java
+++ b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/chunk/ChunkSampleStream.java
@@ -433,7 +433,14 @@ public class ChunkSampleStream<T extends ChunkSource>
   public void onLoadStarted(
       Chunk loadable, long elapsedRealtimeMs, long loadDurationMs, int retryCount) {
     mediaSourceEventDispatcher.loadStarted(
-        new LoadEventInfo(loadable.loadTaskId, loadable.dataSpec, elapsedRealtimeMs),
+        new LoadEventInfo(
+            loadable.loadTaskId,
+            loadable.dataSpec,
+            loadable.getUri(),
+            loadable.getResponseHeaders(),
+            elapsedRealtimeMs,
+            loadDurationMs,
+            /* bytesLoaded= */ 0),
         loadable.type,
         primaryTrackType,
         loadable.trackFormat,
@@ -651,19 +658,8 @@ public class ChunkSampleStream<T extends ChunkSource>
     } else if (loadable instanceof InitializationChunk) {
       ((InitializationChunk) loadable).init(chunkOutput);
     }
-    long elapsedRealtimeMs =
-        loader.startLoading(
-            loadable, this, loadErrorHandlingPolicy.getMinimumLoadableRetryCount(loadable.type));
-    mediaSourceEventDispatcher.loadStarted(
-        new LoadEventInfo(loadable.loadTaskId, loadable.dataSpec, elapsedRealtimeMs),
-        loadable.type,
-        primaryTrackType,
-        loadable.trackFormat,
-        loadable.trackSelectionReason,
-        loadable.trackSelectionData,
-        loadable.startTimeUs,
-        loadable.endTimeUs,
-        /* retryCount= */ 0);
+    loader.startLoading(
+        loadable, this, loadErrorHandlingPolicy.getMinimumLoadableRetryCount(loadable.type));
     return true;
   }
 
diff --git a/libraries/exoplayer_dash/src/main/java/androidx/media3/exoplayer/dash/DashMediaSource.java b/libraries/exoplayer_dash/src/main/java/androidx/media3/exoplayer/dash/DashMediaSource.java
index 701c96dd0c..de8686bb19 100644
--- a/libraries/exoplayer_dash/src/main/java/androidx/media3/exoplayer/dash/DashMediaSource.java
+++ b/libraries/exoplayer_dash/src/main/java/androidx/media3/exoplayer/dash/DashMediaSource.java
@@ -635,7 +635,14 @@ public final class DashMediaSource extends BaseMediaSource {
       long loadDurationMs,
       int retryCount) {
     manifestEventDispatcher.loadStarted(
-        new LoadEventInfo(loadable.loadTaskId, loadable.dataSpec, elapsedRealtimeMs),
+        new LoadEventInfo(
+            loadable.loadTaskId,
+            loadable.dataSpec,
+            loadable.getUri(),
+            loadable.getResponseHeaders(),
+            elapsedRealtimeMs,
+            loadDurationMs,
+            /* bytesLoaded= */ 0),
         loadable.type,
         retryCount);
   }
@@ -1105,11 +1112,7 @@ public final class DashMediaSource extends BaseMediaSource {
       ParsingLoadable<T> loadable,
       Loader.Callback<ParsingLoadable<T>> callback,
       int minRetryCount) {
-    long elapsedRealtimeMs = loader.startLoading(loadable, callback, minRetryCount);
-    manifestEventDispatcher.loadStarted(
-        new LoadEventInfo(loadable.loadTaskId, loadable.dataSpec, elapsedRealtimeMs),
-        loadable.type,
-        /* retryCount= */ 0);
+    loader.startLoading(loadable, callback, minRetryCount);
   }
 
   private static long getIntervalUntilNextManifestRefreshMs(
diff --git a/libraries/exoplayer_hls/src/main/java/androidx/media3/exoplayer/hls/HlsSampleStreamWrapper.java b/libraries/exoplayer_hls/src/main/java/androidx/media3/exoplayer/hls/HlsSampleStreamWrapper.java
index dca0e341ee..9863ced91f 100644
--- a/libraries/exoplayer_hls/src/main/java/androidx/media3/exoplayer/hls/HlsSampleStreamWrapper.java
+++ b/libraries/exoplayer_hls/src/main/java/androidx/media3/exoplayer/hls/HlsSampleStreamWrapper.java
@@ -808,20 +808,8 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
       initMediaChunkLoad((HlsMediaChunk) loadable);
     }
     loadingChunk = loadable;
-    long elapsedRealtimeMs =
-        loader.startLoading(
-            loadable, this, loadErrorHandlingPolicy.getMinimumLoadableRetryCount(loadable.type));
-    // DO NOT SUBMIT is this duplicated with the line in onLoadStarted below on L868?
-    mediaSourceEventDispatcher.loadStarted(
-        new LoadEventInfo(loadable.loadTaskId, loadable.dataSpec, elapsedRealtimeMs),
-        loadable.type,
-        trackType,
-        loadable.trackFormat,
-        loadable.trackSelectionReason,
-        loadable.trackSelectionData,
-        loadable.startTimeUs,
-        loadable.endTimeUs,
-        /* retryCount= */ 0);
+    loader.startLoading(
+        loadable, this, loadErrorHandlingPolicy.getMinimumLoadableRetryCount(loadable.type));
     return true;
   }
 
@@ -866,7 +854,14 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
   public void onLoadStarted(
       Chunk loadable, long elapsedRealtimeMs, long loadDurationMs, int retryCount) {
     mediaSourceEventDispatcher.loadStarted(
-        new LoadEventInfo(loadable.loadTaskId, loadable.dataSpec, elapsedRealtimeMs),
+        new LoadEventInfo(
+            loadable.loadTaskId,
+            loadable.dataSpec,
+            loadable.getUri(),
+            loadable.getResponseHeaders(),
+            elapsedRealtimeMs,
+            loadDurationMs,
+            /* bytesLoaded= */ 0),
         loadable.type,
         trackType,
         loadable.trackFormat,
diff --git a/libraries/exoplayer_hls/src/main/java/androidx/media3/exoplayer/hls/playlist/DefaultHlsPlaylistTracker.java b/libraries/exoplayer_hls/src/main/java/androidx/media3/exoplayer/hls/playlist/DefaultHlsPlaylistTracker.java
index 93942d73df..51c6d04e5e 100644
--- a/libraries/exoplayer_hls/src/main/java/androidx/media3/exoplayer/hls/playlist/DefaultHlsPlaylistTracker.java
+++ b/libraries/exoplayer_hls/src/main/java/androidx/media3/exoplayer/hls/playlist/DefaultHlsPlaylistTracker.java
@@ -141,19 +141,10 @@ public final class DefaultHlsPlaylistTracker
             playlistParserFactory.createPlaylistParser());
     Assertions.checkState(initialPlaylistLoader == null);
     initialPlaylistLoader = new Loader("DefaultHlsPlaylistTracker:MultivariantPlaylist");
-    long elapsedRealtime =
-        initialPlaylistLoader.startLoading(
-            multivariantPlaylistLoadable,
-            this,
-            loadErrorHandlingPolicy.getMinimumLoadableRetryCount(
-                multivariantPlaylistLoadable.type));
-    eventDispatcher.loadStarted(
-        new LoadEventInfo(
-            multivariantPlaylistLoadable.loadTaskId,
-            multivariantPlaylistLoadable.dataSpec,
-            elapsedRealtime),
-        multivariantPlaylistLoadable.type,
-        /* retryCount= */ 0);
+    initialPlaylistLoader.startLoading(
+        multivariantPlaylistLoadable,
+        this,
+        loadErrorHandlingPolicy.getMinimumLoadableRetryCount(multivariantPlaylistLoadable.type));
   }
 
   @Override
@@ -262,7 +253,14 @@ public final class DefaultHlsPlaylistTracker
       long loadDurationMs,
       int retryCount) {
     eventDispatcher.loadStarted(
-        new LoadEventInfo(loadable.loadTaskId, loadable.dataSpec, elapsedRealtimeMs),
+        new LoadEventInfo(
+            loadable.loadTaskId,
+            loadable.dataSpec,
+            loadable.getUri(),
+            loadable.getResponseHeaders(),
+            elapsedRealtimeMs,
+            loadDurationMs,
+            /* bytesLoaded= */ 0),
         loadable.type,
         retryCount);
   }
@@ -749,16 +747,10 @@ public final class DefaultHlsPlaylistTracker
               playlistRequestUri,
               C.DATA_TYPE_MANIFEST,
               mediaPlaylistParser);
-      long elapsedRealtime =
           mediaPlaylistLoader.startLoading(
               mediaPlaylistLoadable,
               /* callback= */ this,
               loadErrorHandlingPolicy.getMinimumLoadableRetryCount(mediaPlaylistLoadable.type));
-      eventDispatcher.loadStarted(
-          new LoadEventInfo(
-              mediaPlaylistLoadable.loadTaskId, mediaPlaylistLoadable.dataSpec, elapsedRealtime),
-          mediaPlaylistLoadable.type,
-          /* retryCount= */ 0);
     }
 
     private void processLoadedPlaylist(
diff --git a/libraries/exoplayer_smoothstreaming/src/main/java/androidx/media3/exoplayer/smoothstreaming/SsMediaSource.java b/libraries/exoplayer_smoothstreaming/src/main/java/androidx/media3/exoplayer/smoothstreaming/SsMediaSource.java
index 8f5f12bbbd..a8e9498740 100644
--- a/libraries/exoplayer_smoothstreaming/src/main/java/androidx/media3/exoplayer/smoothstreaming/SsMediaSource.java
+++ b/libraries/exoplayer_smoothstreaming/src/main/java/androidx/media3/exoplayer/smoothstreaming/SsMediaSource.java
@@ -504,7 +504,14 @@ public final class SsMediaSource extends BaseMediaSource
       long loadDurationMs,
       int retryCount) {
     manifestEventDispatcher.loadStarted(
-        new LoadEventInfo(loadable.loadTaskId, loadable.dataSpec, elapsedRealtimeMs),
+        new LoadEventInfo(
+            loadable.loadTaskId,
+            loadable.dataSpec,
+            loadable.getUri(),
+            loadable.getResponseHeaders(),
+            elapsedRealtimeMs,
+            loadDurationMs,
+            /* bytesLoaded= */ 0),
         loadable.type,
         /* retryCount= */ 0);
   }