diff --git a/src/Sound/beacon.hxx b/src/Sound/beacon.hxx
index 7d2acfae5..6c7021420 100644
--- a/src/Sound/beacon.hxx
+++ b/src/Sound/beacon.hxx
@@ -33,9 +33,6 @@
 #include <simgear/compiler.h>
 #include <simgear/sound/soundmgr_openal.hxx>
 
-#include <plib/sl.h>
-#include <plib/sm.h>
-
 #include "morse.hxx"