diff --git a/src/modules/systemlib/mixer/mixer_load.c b/src/modules/systemlib/mixer/mixer_load.c
index b05273c0de..bf3428a50b 100644
--- a/src/modules/systemlib/mixer/mixer_load.c
+++ b/src/modules/systemlib/mixer/mixer_load.c
@@ -41,6 +41,7 @@
 #include <string.h>
 #include <stdio.h>
 #include <ctype.h>
+#include <systemlib/err.h>
 
 #include "mixer_load.h"