diff --git a/zsnes/src/gui/guikeys.inc b/zsnes/src/gui/guikeys.inc
index 47e8ac26..a5f2dcfe 100644
--- a/zsnes/src/gui/guikeys.inc
+++ b/zsnes/src/gui/guikeys.inc
@@ -896,6 +896,7 @@ GUIOptionKeys:
     cmp dh,'S'
     jne .noalttimer
     xor byte[AlternateTimer],1
+    call guimustrestartmsg
 .noalttimer
 %endif
     ret