diff --git a/protocols/rdp/include/audio.h b/protocols/rdp/include/audio.h
index d5dd8eb1..fb441f2a 100644
--- a/protocols/rdp/include/audio.h
+++ b/protocols/rdp/include/audio.h
@@ -151,6 +151,11 @@ struct audio_stream {
      */
     int bps;
 
+    /**
+     * Encoder-specific state data.
+     */
+    void* data;
+
 };
 
 /**