diff --git a/apps/px4io/mixer.cpp b/apps/px4io/mixer.cpp
index 092a35a443..ec69cdd64e 100644
--- a/apps/px4io/mixer.cpp
+++ b/apps/px4io/mixer.cpp
@@ -38,6 +38,7 @@
  */
 
 #include <nuttx/config.h>
+#include <syslog.h>
 
 #include <sys/types.h>
 #include <stdbool.h>