diff --git a/media/libaudioprocessing/AudioMixer.cpp b/media/libaudioprocessing/AudioMixer.cpp
index 07b2520..e6fdb1d 100644
--- a/media/libaudioprocessing/AudioMixer.cpp
+++ b/media/libaudioprocessing/AudioMixer.cpp
@@ -188,6 +188,24 @@
         // mDownmixerBufferProvider reset below.
     }
 
+    // See if we should use our built-in non-effect downmixer.
+    if (mMixerInFormat == AUDIO_FORMAT_PCM_FLOAT
+            && mMixerChannelMask == AUDIO_CHANNEL_OUT_STEREO
+            && audio_channel_mask_get_representation(channelMask)
+                    == AUDIO_CHANNEL_REPRESENTATION_POSITION) {
+        mDownmixerBufferProvider.reset(new ChannelMixBufferProvider(channelMask,
+                mMixerChannelMask, mMixerInFormat, kCopyBufferFrameCount));
+        if (static_cast<ChannelMixBufferProvider *>(mDownmixerBufferProvider.get())
+                ->isValid()) {
+            mDownmixRequiresFormat = mMixerInFormat;
+            reconfigureBufferProviders();
+            ALOGD("%s: Fallback using ChannelMix", __func__);
+            return NO_ERROR;
+        } else {
+            ALOGD("%s: ChannelMix not supported for channel mask %#x", __func__, channelMask);
+        }
+    }
+
     // Effect downmixer does not accept the channel conversion.  Let's use our remixer.
     mDownmixerBufferProvider.reset(new RemixBufferProvider(channelMask,
             mMixerChannelMask, mMixerInFormat, kCopyBufferFrameCount));
diff --git a/media/libaudioprocessing/BufferProviders.cpp b/media/libaudioprocessing/BufferProviders.cpp
index 0114355..4658db8 100644
--- a/media/libaudioprocessing/BufferProviders.cpp
+++ b/media/libaudioprocessing/BufferProviders.cpp
@@ -364,6 +364,29 @@
             src, mInputChannels, mIdxAry, mSampleSize, frames);
 }
 
+ChannelMixBufferProvider::ChannelMixBufferProvider(audio_channel_mask_t inputChannelMask,
+        audio_channel_mask_t outputChannelMask, audio_format_t format,
+        size_t bufferFrameCount) :
+        CopyBufferProvider(
+                audio_bytes_per_sample(format)
+                    * audio_channel_count_from_out_mask(inputChannelMask),
+                audio_bytes_per_sample(format)
+                    * audio_channel_count_from_out_mask(outputChannelMask),
+                bufferFrameCount)
+{
+    ALOGV("ChannelMixBufferProvider(%p)(%#x, %#x, %#x)",
+            this, format, inputChannelMask, outputChannelMask);
+    if (outputChannelMask == AUDIO_CHANNEL_OUT_STEREO && format == AUDIO_FORMAT_PCM_FLOAT) {
+        mIsValid = mChannelMix.setInputChannelMask(inputChannelMask);
+    }
+}
+
+void ChannelMixBufferProvider::copyFrames(void *dst, const void *src, size_t frames)
+{
+    mChannelMix.process(static_cast<const float *>(src), static_cast<float *>(dst),
+            frames, false /* accumulate */);
+}
+
 ReformatBufferProvider::ReformatBufferProvider(int32_t channelCount,
         audio_format_t inputFormat, audio_format_t outputFormat,
         size_t bufferFrameCount) :
diff --git a/media/libaudioprocessing/include/media/BufferProviders.h b/media/libaudioprocessing/include/media/BufferProviders.h
index 525ab8c..b3ab8a5 100644
--- a/media/libaudioprocessing/include/media/BufferProviders.h
+++ b/media/libaudioprocessing/include/media/BufferProviders.h
@@ -20,6 +20,7 @@
 #include <stdint.h>
 #include <sys/types.h>
 
+#include <audio_utils/ChannelMix.h>
 #include <media/AudioBufferProvider.h>
 #include <media/AudioResamplerPublic.h>
 #include <system/audio.h>
@@ -129,6 +130,23 @@
     static const int32_t SESSION_ID_INVALID_AND_IGNORED = -2;
 };
 
+// ChannelMixBufferProvider derives from CopyBufferProvider to perform an
+// downmix to the proper channel count and mask.
+class ChannelMixBufferProvider : public CopyBufferProvider {
+public:
+    ChannelMixBufferProvider(audio_channel_mask_t inputChannelMask,
+            audio_channel_mask_t outputChannelMask, audio_format_t format,
+            size_t bufferFrameCount);
+
+    void copyFrames(void *dst, const void *src, size_t frames) override;
+
+    bool isValid() const { return mIsValid; }
+
+protected:
+    audio_utils::channels::ChannelMix mChannelMix;
+    bool mIsValid = false;
+};
+
 // RemixBufferProvider derives from CopyBufferProvider to perform an
 // upmix or downmix to the proper channel count and mask.
 class RemixBufferProvider : public CopyBufferProvider {