diff --git a/src/output/plugins/RecorderOutputPlugin.cxx b/src/output/plugins/RecorderOutputPlugin.cxx
index 5f6a55418..295fb948c 100644
--- a/src/output/plugins/RecorderOutputPlugin.cxx
+++ b/src/output/plugins/RecorderOutputPlugin.cxx
@@ -31,7 +31,9 @@
 
 #include <assert.h>
 
-struct RecorderOutput {
+class RecorderOutput {
+	friend struct AudioOutputWrapper<RecorderOutput>;
+
 	AudioOutput base;
 
 	/**