Add virtual destructor.
diff --git a/libs/audioflinger/AudioBufferProvider.h b/libs/audioflinger/AudioBufferProvider.h
index 1a467c7..81c5c39 100644
--- a/libs/audioflinger/AudioBufferProvider.h
+++ b/libs/audioflinger/AudioBufferProvider.h
@@ -36,6 +36,8 @@
         };
         size_t frameCount;
     };
+
+    virtual ~AudioBufferProvider() {}
     
     virtual status_t getNextBuffer(Buffer* buffer) = 0;
     virtual void releaseBuffer(Buffer* buffer) = 0;