diff --git a/services/audioflinger/Effects.h b/services/audioflinger/Effects.h
index 9da95bc..661881e 100644
--- a/services/audioflinger/Effects.h
+++ b/services/audioflinger/Effects.h
@@ -138,8 +138,9 @@
                              int32_t __unused,
                              std::vector<uint8_t>* __unused) { return NO_ERROR; };
 
+    // mCallback is atomic so this can be lock-free.
     void setCallback(const sp<EffectCallbackInterface>& callback) { mCallback = callback; }
-    sp<EffectCallbackInterface>&     callback() { return mCallback; }
+    sp<EffectCallbackInterface> getCallback() const { return mCallback.load(); }
 
     status_t addHandle(EffectHandle *handle);
     ssize_t disconnectHandle(EffectHandle *handle, bool unpinIfLast);
@@ -170,7 +171,7 @@
     DISALLOW_COPY_AND_ASSIGN(EffectBase);
 
 mutable Mutex                 mLock;      // mutex for process, commands and handles list protection
-    sp<EffectCallbackInterface> mCallback; // parent effect chain
+    mediautils::atomic_sp<EffectCallbackInterface> mCallback; // parent effect chain
     const int                 mId;        // this instance unique ID
     const audio_session_t     mSessionId; // audio session ID
     const effect_descriptor_t mDescriptor;// effect descriptor received from effect engine