diff --git a/RELEASENOTES.md b/RELEASENOTES.md
index 602c823c891..d50686f2981 100644
--- a/RELEASENOTES.md
+++ b/RELEASENOTES.md
@@ -17,6 +17,8 @@
   ([#6396](https://github.com/google/ExoPlayer/issues/6396)).
 * Fix audio selection issue where languages are compared by bit rate
   ([#6335](https://github.com/google/ExoPlayer/issues/6335)).
+* Fix decoder selection for E-AC3 JOC streams
+  ([#6398](https://github.com/google/ExoPlayer/issues/6398)).
 * Fix `PlayerNotificationManager` to show play icon rather than pause icon when
   playback is ended ([#6324](https://github.com/google/ExoPlayer/issues/6324)).
 * Upgrade LibRtmp-Client-for-Android to fix RTMP playback issues
diff --git a/library/core/src/main/java/com/google/android/exoplayer2/audio/MediaCodecAudioRenderer.java b/library/core/src/main/java/com/google/android/exoplayer2/audio/MediaCodecAudioRenderer.java
index 07a1438519c..f10f45ecf30 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/audio/MediaCodecAudioRenderer.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/audio/MediaCodecAudioRenderer.java
@@ -45,6 +45,7 @@
 import com.google.android.exoplayer2.util.MimeTypes;
 import com.google.android.exoplayer2.util.Util;
 import java.nio.ByteBuffer;
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 
@@ -369,10 +370,11 @@ protected List<MediaCodecInfo> getDecoderInfos(
             format.sampleMimeType, requiresSecureDecoder, /* requiresTunnelingDecoder= */ false);
     if (MimeTypes.AUDIO_E_AC3_JOC.equals(format.sampleMimeType)) {
       // E-AC3 decoders can decode JOC streams, but in 2-D rather than 3-D.
-      List<MediaCodecInfo> eac3DecoderInfos =
+      List<MediaCodecInfo> decoderInfosWithEac3 = new ArrayList<>(decoderInfos);
+      decoderInfosWithEac3.addAll(
           mediaCodecSelector.getDecoderInfos(
-              MimeTypes.AUDIO_E_AC3, requiresSecureDecoder, /* requiresTunnelingDecoder= */ false);
-      decoderInfos.addAll(eac3DecoderInfos);
+              MimeTypes.AUDIO_E_AC3, requiresSecureDecoder, /* requiresTunnelingDecoder= */ false));
+      decoderInfos = decoderInfosWithEac3;
     }
     return Collections.unmodifiableList(decoderInfos);
   }
diff --git a/library/core/src/main/java/com/google/android/exoplayer2/mediacodec/MediaCodecSelector.java b/library/core/src/main/java/com/google/android/exoplayer2/mediacodec/MediaCodecSelector.java
index 41cb4ee04a0..c6e93d104a3 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/mediacodec/MediaCodecSelector.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/mediacodec/MediaCodecSelector.java
@@ -51,7 +51,8 @@ public List<MediaCodecInfo> getDecoderInfos(
    * @param mimeType The MIME type for which a decoder is required.
    * @param requiresSecureDecoder Whether a secure decoder is required.
    * @param requiresTunnelingDecoder Whether a tunneling decoder is required.
-   * @return A list of {@link MediaCodecInfo}s corresponding to decoders. May be empty.
+   * @return An unmodifiable list of {@link MediaCodecInfo}s corresponding to decoders. May be
+   *     empty.
    * @throws DecoderQueryException Thrown if there was an error querying decoders.
    */
   List<MediaCodecInfo> getDecoderInfos(
diff --git a/library/core/src/main/java/com/google/android/exoplayer2/mediacodec/MediaCodecUtil.java b/library/core/src/main/java/com/google/android/exoplayer2/mediacodec/MediaCodecUtil.java
index a6391e4cc71..671523b5e81 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/mediacodec/MediaCodecUtil.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/mediacodec/MediaCodecUtil.java
@@ -146,8 +146,8 @@ public static MediaCodecInfo getDecoderInfo(String mimeType, boolean secure, boo
    *     unless secure decryption really is required.
    * @param tunneling Whether the decoder is required to support tunneling. Always pass false unless
    *     tunneling really is required.
-   * @return A list of all {@link MediaCodecInfo}s for the given mime type, in the order given by
-   *     {@link MediaCodecList}.
+   * @return An unmodifiable list of all {@link MediaCodecInfo}s for the given mime type, in the
+   *     order given by {@link MediaCodecList}.
    * @throws DecoderQueryException If there was an error querying the available decoders.
    */
   public static synchronized List<MediaCodecInfo> getDecoderInfos(