diff --git a/services/oboeservice/AAudioServiceEndpoint.h b/services/oboeservice/AAudioServiceEndpoint.h
index d0c2f53..50bf049 100644
--- a/services/oboeservice/AAudioServiceEndpoint.h
+++ b/services/oboeservice/AAudioServiceEndpoint.h
@@ -23,6 +23,7 @@
 #include <vector>
 
 #include "client/AudioStreamInternal.h"
+#include "client/AudioStreamInternalPlay.h"
 #include "binding/AAudioServiceMessage.h"
 #include "AAudioServiceStreamShared.h"
 #include "AAudioServiceStreamMMAP.h"
@@ -33,14 +34,13 @@
 
 class AAudioServiceEndpoint {
 public:
-    explicit AAudioServiceEndpoint(android::AAudioService &audioService);
-    virtual ~AAudioServiceEndpoint();
+    virtual ~AAudioServiceEndpoint() = default;
 
-    aaudio_result_t open(int32_t deviceId, aaudio_direction_t direction);
+    virtual aaudio_result_t open(int32_t deviceId);
 
-    int32_t getSampleRate() const { return mStreamInternal.getSampleRate(); }
-    int32_t getSamplesPerFrame() const { return mStreamInternal.getSamplesPerFrame();  }
-    int32_t getFramesPerBurst() const { return mStreamInternal.getFramesPerBurst();  }
+    int32_t getSampleRate() const { return mStreamInternal->getSampleRate(); }
+    int32_t getSamplesPerFrame() const { return mStreamInternal->getSamplesPerFrame();  }
+    int32_t getFramesPerBurst() const { return mStreamInternal->getFramesPerBurst();  }
 
     aaudio_result_t registerStream(AAudioServiceStreamShared *sharedStream);
     aaudio_result_t unregisterStream(AAudioServiceStreamShared *sharedStream);
@@ -48,13 +48,13 @@
     aaudio_result_t stopStream(AAudioServiceStreamShared *sharedStream);
     aaudio_result_t close();
 
-    int32_t getDeviceId() const { return mStreamInternal.getDeviceId(); }
+    int32_t getDeviceId() const { return mStreamInternal->getDeviceId(); }
 
-    aaudio_direction_t getDirection() const { return mStreamInternal.getDirection(); }
+    aaudio_direction_t getDirection() const { return mStreamInternal->getDirection(); }
 
     void disconnectRegisteredStreams();
 
-    void *callbackLoop();
+    virtual void *callbackLoop() = 0;
 
     // This should only be called from the AAudioEndpointManager under a mutex.
     int32_t getReferenceCount() const {
@@ -66,23 +66,21 @@
         mReferenceCount = count;
     }
 
-private:
-    aaudio_result_t startMixer_l();
-    aaudio_result_t stopMixer_l();
-
-    int64_t calculateReasonableTimeout(int32_t framesPerOperation);
-
-    AudioStreamInternal      mStreamInternal;
-    AAudioMixer              mMixer;
+    virtual AudioStreamInternal *getStreamInternal() = 0;
 
     std::atomic<bool>        mCallbackEnabled;
-    int32_t                  mReferenceCount = 0;
-    bool                     mLatencyTuningEnabled = false; // TODO implement tuning
 
     std::mutex               mLockStreams;
+
     std::vector<AAudioServiceStreamShared *> mRegisteredStreams;
     std::vector<AAudioServiceStreamShared *> mRunningStreams;
 
+private:
+    aaudio_result_t startSharingThread_l();
+    aaudio_result_t stopSharingThread();
+
+    AudioStreamInternal     *mStreamInternal = nullptr;
+    int32_t                  mReferenceCount = 0;
 };
 
 } /* namespace aaudio */