diff --git a/services/oboeservice/AAudioServiceStreamBase.h b/services/oboeservice/AAudioServiceStreamBase.h
index ffc768b..097bc64 100644
--- a/services/oboeservice/AAudioServiceStreamBase.h
+++ b/services/oboeservice/AAudioServiceStreamBase.h
@@ -312,6 +312,12 @@
     android::wp<AAudioServiceEndpoint> mServiceEndpointWeak;
 
 private:
+
+    /**
+     * @return true if the queue is getting full.
+     */
+    bool isUpMessageQueueBusy();
+
     aaudio_handle_t         mHandle = -1;
     bool                    mFlowing = false;