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);
 };