diff --git a/demo/index.html b/demo/index.html
index b8d8d82..fd83edf 100644
--- a/demo/index.html
+++ b/demo/index.html
@@ -356,6 +356,7 @@
             narrow: false,
             autoplay: true,
             showlrc: false,
+            mutex: true,
             theme: '#e6d0b2',
             music: {
                 title: 'Preparation',
@@ -371,6 +372,7 @@
             narrow: true,
             autoplay: false,
             showlrc: false,
+            mutex: true,
             theme: '#e6d0b2',
             music: {
                 title: 'Preparation',
@@ -386,6 +388,7 @@
             narrow: false,
             autoplay: false,
             showlrc: true,
+            mutex: true,
             theme: '#615754',
             music: {
                 title: '回レ！雪月花',
@@ -401,6 +404,7 @@
             narrow: false,
             autoplay: false,
             showlrc: false,
+            mutex: true,
             theme: '#ad7a86',
             music: [
                 {
@@ -430,6 +434,7 @@
             narrow: false,
             autoplay: false,
             showlrc: true,
+            mutex: true,
             theme: '#ad7a86',
             music: [
                 {