diff --git a/audio/6.0/IStreamOut.hal b/audio/6.0/IStreamOut.hal
index 941ba61..91668ba 100644
--- a/audio/6.0/IStreamOut.hal
+++ b/audio/6.0/IStreamOut.hal
@@ -276,4 +276,61 @@
      */
     selectPresentation(int32_t presentationId, int32_t programId)
             generates (Result retval);
+
+    /**
+     * Returns the Dual Mono mode presentation setting.
+     *
+     * Optional method
+     *
+     * @return retval operation completion status.
+     * @return mode current setting of Dual Mono mode.
+     */
+    getDualMonoMode() generates (Result retval, DualMonoMode mode);
+
+    /**
+     * Sets the Dual Mono mode presentation on the output device.
+     *
+     * The Dual Mono mode is generally applied to stereo audio streams
+     * where the left and right channels come from separate sources.
+     *
+     * Optional method
+     *
+     * @param mode selected Dual Mono mode.
+     * @return retval operation completion status.
+     */
+    setDualMonoMode(DualMonoMode mode) generates (Result retval);
+
+    /**
+     * Returns the Audio Description Mix level in dB.
+     *
+     * The level is applied to streams incorporating a secondary Audio
+     * Description stream. It specifies the relative level of mixing for
+     * the Audio Description with a reference to the Main Audio.
+     *
+     * Optional method
+     *
+     * The value of the relative level is in the range from negative infinity
+     * to +48.
+     *
+     * @return retval operation completion status.
+     * @return leveldB the current Audio Description Mix Level in dB.
+     */
+    getAudioDescriptionMixLevel() generates (Result retval, float leveldB);
+
+    /**
+     * Sets the Audio Description Mix level in dB.
+     *
+     * For streams incorporating a secondary Audio Description stream
+     * the relative level of mixing of the Audio Description to the Main Audio
+     * is controlled by this method.
+     *
+     * Optional method
+     *
+     * The value of the relative level must be in the range from negative
+     * infinity to +48.
+     *
+     * @param leveldB Audio Description Mix Level in dB
+     * @return retval operation completion status.
+     */
+    setAudioDescriptionMixLevel(float leveldB) generates (Result retval);
 };
diff --git a/audio/6.0/types.hal b/audio/6.0/types.hal
index 1a704f8..efc3ea5 100644
--- a/audio/6.0/types.hal
+++ b/audio/6.0/types.hal
@@ -247,3 +247,53 @@
      */
     EXTERNAL = 3,
 };
+
+
+/* Dual Mono handling is used when a stereo audio stream
+ * contains separate audio content on the left and right channels.
+ * Such information about the content of the stream may be found, for example,
+ * in ITU T-REC-J.94-201610 A.6.2.3 Component descriptor.
+ */
+@export(name="audio_dual_mono_mode_t", value_prefix="AUDIO_DUAL_MONO_MODE_")
+enum DualMonoMode : int32_t {
+    // Need to be in sync with DUAL_MONO_MODE* constants in
+    // frameworks/base/media/java/android/media/AudioTrack.java
+    /**
+     * Disable any Dual Mono presentation effect.
+     *
+     */
+    OFF = 0,
+    /**
+     * This mode indicates that a stereo stream should be presented
+     * with the left and right audio channels blended together
+     * and delivered to both channels.
+     *
+     * Behavior for non-stereo streams is implementation defined.
+     * A suggested guideline is that the left-right stereo symmetric
+     * channels are pairwise blended, the other channels such as center
+     * are left alone.
+     */
+    LR = 1,
+    /**
+     * This mode indicates that a stereo stream should be presented
+     * with the left audio channel replicated into the right audio channel.
+     *
+     * Behavior for non-stereo streams is implementation defined.
+     * A suggested guideline is that all channels with left-right
+     * stereo symmetry will have the left channel position replicated
+     * into the right channel position. The center channels (with no
+     * left/right symmetry) or unbalanced channels are left alone.
+     */
+    LL = 2,
+    /**
+     * This mode indicates that a stereo stream should be presented
+     * with the right audio channel replicated into the left audio channel.
+     *
+     * Behavior for non-stereo streams is implementation defined.
+     * A suggested guideline is that all channels with left-right
+     * stereo symmetry will have the right channel position replicated
+     * into the left channel position. The center channels (with no
+     * left/right symmetry) or unbalanced channels are left alone.
+     */
+    RR = 3,
+};