diff --git a/src/audio_core/time_stretch.h b/src/audio_core/time_stretch.h
index fa81718ed7..e3e4dc353a 100644
--- a/src/audio_core/time_stretch.h
+++ b/src/audio_core/time_stretch.h
@@ -2,6 +2,8 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
+#pragma once
+
 #include <cstddef>
 #include <memory>
 #include <vector>