diff --git a/libraries/exoplayer/src/test/java/androidx/media3/exoplayer/e2etest/OggOpusPlaybackTest.java b/libraries/exoplayer/src/test/java/androidx/media3/exoplayer/e2etest/OggOpusPlaybackTest.java
index 610747b0bc..c5263a2de6 100644
--- a/libraries/exoplayer/src/test/java/androidx/media3/exoplayer/e2etest/OggOpusPlaybackTest.java
+++ b/libraries/exoplayer/src/test/java/androidx/media3/exoplayer/e2etest/OggOpusPlaybackTest.java
@@ -145,6 +145,7 @@ public final class OggOpusPlaybackTest {
     }
   }
 
+  // TODO: b/406216855 - Remove this and use CapturingAudioSink instead.
   private static final class DumpingAudioSink extends ForwardingAudioSink
       implements Dumper.Dumpable {
     /** All handleBuffer interactions recorded with this audio sink. */
diff --git a/libraries/test_utils/src/main/java/androidx/media3/test/utils/CapturingAudioSink.java b/libraries/test_utils/src/main/java/androidx/media3/test/utils/CapturingAudioSink.java
index dc869ee5ea..44cb062ac1 100644
--- a/libraries/test_utils/src/main/java/androidx/media3/test/utils/CapturingAudioSink.java
+++ b/libraries/test_utils/src/main/java/androidx/media3/test/utils/CapturingAudioSink.java
@@ -168,10 +168,11 @@ public class CapturingAudioSink extends ForwardingAudioSink implements Dumper.Du
           && !inputFormat.sampleMimeType.equals(MimeTypes.AUDIO_RAW)) {
         dumper.add("mimeType", inputFormat.sampleMimeType);
       }
+
       dumper
-          .add("pcmEncoding", inputFormat.pcmEncoding)
-          .add("channelCount", inputFormat.channelCount)
-          .add("sampleRate", inputFormat.sampleRate);
+          .addIfNonDefault("pcmEncoding", inputFormat.pcmEncoding, Format.NO_VALUE)
+          .addIfNonDefault("channelCount", inputFormat.channelCount, Format.NO_VALUE)
+          .addIfNonDefault("sampleRate", inputFormat.sampleRate, Format.NO_VALUE);
       if (outputChannels != null) {
         dumper.add("outputChannels", Arrays.toString(outputChannels));
       }