diff --git a/services/audioflinger/FastMixer.cpp b/services/audioflinger/FastMixer.cpp
index d15841f..f328577 100644
--- a/services/audioflinger/FastMixer.cpp
+++ b/services/audioflinger/FastMixer.cpp
@@ -37,8 +37,9 @@
 #include <cpustats/ThreadCpuUsage.h>
 #endif
 #endif
-#include <audio_utils/mono_blend.h>
+#include <audio_utils/channels.h>
 #include <audio_utils/format.h>
+#include <audio_utils/mono_blend.h>
 #include <media/AudioMixer.h>
 #include "FastMixer.h"
 #include "TypedLogger.h"
@@ -159,20 +160,24 @@
     if (current->mOutputSinkGen != mOutputSinkGen) {
         mOutputSink = current->mOutputSink;
         mOutputSinkGen = current->mOutputSinkGen;
+        mSinkChannelMask = current->mSinkChannelMask;
         if (mOutputSink == NULL) {
             mFormat = Format_Invalid;
             mSampleRate = 0;
             mSinkChannelCount = 0;
             mSinkChannelMask = AUDIO_CHANNEL_NONE;
+            mAudioChannelCount = 0;
         } else {
             mFormat = mOutputSink->format();
             mSampleRate = Format_sampleRate(mFormat);
             mSinkChannelCount = Format_channelCount(mFormat);
             LOG_ALWAYS_FATAL_IF(mSinkChannelCount > AudioMixer::MAX_NUM_CHANNELS);
 
-            // TODO: Add channel mask to NBAIO_Format
-            // We assume that the channel mask must be a valid positional channel mask.
-            mSinkChannelMask = audio_channel_out_mask_from_count(mSinkChannelCount);
+            if (mSinkChannelMask == AUDIO_CHANNEL_NONE) {
+                mSinkChannelMask = audio_channel_out_mask_from_count(mSinkChannelCount);
+            }
+            mAudioChannelCount = mSinkChannelCount - audio_channel_count_from_out_mask(
+                    mSinkChannelMask & AUDIO_CHANNEL_HAPTIC_ALL);
         }
         dumpState->mSampleRate = mSampleRate;
     }
@@ -288,6 +293,8 @@
                         (void *)(uintptr_t)fastTrack->mChannelMask);
                 mMixer->setParameter(name, AudioMixer::TRACK, AudioMixer::MIXER_CHANNEL_MASK,
                         (void *)(uintptr_t)mSinkChannelMask);
+                mMixer->setParameter(name, AudioMixer::TRACK, AudioMixer::HAPTIC_ENABLED,
+                        (void *)(uintptr_t)fastTrack->mHapticPlaybackEnabled);
                 mMixer->enable(name);
             }
             mGenerations[i] = fastTrack->mGeneration;
@@ -324,6 +331,8 @@
                             (void *)(uintptr_t)fastTrack->mChannelMask);
                     mMixer->setParameter(name, AudioMixer::TRACK, AudioMixer::MIXER_CHANNEL_MASK,
                             (void *)(uintptr_t)mSinkChannelMask);
+                    mMixer->setParameter(name, AudioMixer::TRACK, AudioMixer::HAPTIC_ENABLED,
+                            (void *)(uintptr_t)fastTrack->mHapticPlaybackEnabled);
                     // already enabled
                 }
                 mGenerations[i] = fastTrack->mGeneration;
@@ -468,6 +477,13 @@
             memcpy_by_audio_format(buffer, mFormat.mFormat, mMixerBuffer, mMixerBufferFormat,
                     frameCount * Format_channelCount(mFormat));
         }
+        if (mSinkChannelMask & AUDIO_CHANNEL_HAPTIC_ALL) {
+            // When there are haptic channels, the sample data is partially interleaved.
+            // Make the sample data fully interleaved here.
+            adjust_channels_non_destructive(buffer, mAudioChannelCount, buffer, mSinkChannelCount,
+                    audio_bytes_per_sample(mFormat.mFormat),
+                    frameCount * audio_bytes_per_frame(mAudioChannelCount, mFormat.mFormat));
+        }
         // if non-NULL, then duplicate write() to this non-blocking sink
 #ifdef TEE_SINK
         mTee.write(buffer, frameCount);