diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8aded823..dac8c645 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,11 +6,13 @@ en-US:
 
 - Automatically use the default configuration if the Profile does not exist on Windows
 - Add ToolTip to the connection bar
+- Add system beep support
 
 zh-CN:
 
 - Windows下Profile如果不存在则自动使用默认配置
 - 增加连接条ToolTip显示
+- 增加系统响铃支持
 
 ## [[V0.5.0](https://github.com/QQxiaoming/quardCRT/releases/tag/V0.5.0)] - 2024-08-26
 
diff --git a/docs/changelog.md b/docs/changelog.md
index 8d1479b7..5d94378c 100644
--- a/docs/changelog.md
+++ b/docs/changelog.md
@@ -6,6 +6,7 @@
 
 - Automatically use the default configuration if the Profile does not exist on Windows
 - Add ToolTip to the connection bar
+- Add system beep support
 
 ## [[V0.5.0](https://github.com/QQxiaoming/quardCRT/releases/tag/V0.5.0)] - 2024-08-26
 
diff --git a/lib/qtermwidget/Filter.cpp b/lib/qtermwidget/Filter.cpp
index 48aea2a8..d750d856 100644
--- a/lib/qtermwidget/Filter.cpp
+++ b/lib/qtermwidget/Filter.cpp
@@ -39,8 +39,7 @@
 
 FilterChain::~FilterChain()
 {
-    while (!isEmpty())
-        delete takeFirst();
+
 }
 
 void FilterChain::addFilter(Filter* filter)
diff --git a/lib/qtermwidget/qtermwidget.cpp b/lib/qtermwidget/qtermwidget.cpp
index 69f9afed..814ca248 100644
--- a/lib/qtermwidget/qtermwidget.cpp
+++ b/lib/qtermwidget/qtermwidget.cpp
@@ -51,7 +51,7 @@ QTermWidget::QTermWidget(QWidget *messageParentWidget, QWidget *parent)
 
     m_terminalDisplay = new TerminalDisplay(this);
     m_emulation = new Vt102Emulation();
-    m_terminalDisplay->setBellMode(TerminalDisplay::NotifyBell);
+    m_terminalDisplay->setBellMode(TerminalDisplay::SystemBeepBell);
     m_terminalDisplay->setTerminalSizeHint(true);
     m_terminalDisplay->setTripleClickMode(TerminalDisplay::SelectWholeLine);
     m_terminalDisplay->setTerminalSizeStartup(true);
@@ -110,9 +110,9 @@ QTermWidget::QTermWidget(QWidget *messageParentWidget, QWidget *parent)
     connect( m_emulation, &Emulation::cursorChanged, this, &QTermWidget::cursorChanged);
 
     // That's OK, FilterChain's dtor takes care of UrlFilter.
-    urlFilter = new UrlFilter();
-    connect(urlFilter, &UrlFilter::activated, this, &QTermWidget::urlActivated);
-    m_terminalDisplay->filterChain()->addFilter(urlFilter);
+    m_urlFilter = new UrlFilter();
+    connect(m_urlFilter, &UrlFilter::activated, this, &QTermWidget::urlActivated);
+    m_terminalDisplay->filterChain()->addFilter(m_urlFilter);
     m_UrlFilterEnable = true;
 
     m_searchBar = new SearchBar(this);
@@ -165,8 +165,9 @@ QTermWidget::QTermWidget(QWidget *messageParentWidget, QWidget *parent)
 
 QTermWidget::~QTermWidget()
 {
-    setUrlFilterEnabled(true);
+    setUrlFilterEnabled(false);
     clearHighLightTexts();
+    delete m_urlFilter;
     delete m_searchBar;
     emit destroyed();
     delete m_emulation;
@@ -466,7 +467,7 @@ void QTermWidget::monitorTimerDone()
 void QTermWidget::activityStateSet(int state)
 {
     if (state==NOTIFYBELL) {
-        m_terminalDisplay->bell(tr("Bell in session"));
+        m_terminalDisplay->bell("Bell in QTermWidget!");
     } else if (state==NOTIFYACTIVITY) {
         if (m_monitorSilence) {
             m_monitorTimer->start(m_silenceSeconds*1000);
@@ -954,9 +955,9 @@ void QTermWidget::setUrlFilterEnabled(bool enable) {
         return;
     }
     if(enable) {
-        m_terminalDisplay->filterChain()->addFilter(urlFilter);
+        m_terminalDisplay->filterChain()->addFilter(m_urlFilter);
     } else {
-        m_terminalDisplay->filterChain()->removeFilter(urlFilter);
+        m_terminalDisplay->filterChain()->removeFilter(m_urlFilter);
     }
 }
 
diff --git a/lib/qtermwidget/qtermwidget.h b/lib/qtermwidget/qtermwidget.h
index 9fe34682..a3d0e015 100644
--- a/lib/qtermwidget/qtermwidget.h
+++ b/lib/qtermwidget/qtermwidget.h
@@ -374,11 +374,11 @@ private slots:
     QWidget *messageParentWidget = nullptr;
     TerminalDisplay *m_terminalDisplay = nullptr;
     Emulation  *m_emulation = nullptr;
-    SearchBar* m_searchBar;
-    QVBoxLayout *m_layout;
+    SearchBar* m_searchBar = nullptr;
+    QVBoxLayout *m_layout = nullptr;
     QList<HighLightText*> m_highLightTexts;
     bool m_echo = false;
-    UrlFilter *urlFilter = nullptr;
+    UrlFilter *m_urlFilter = nullptr;
     bool m_UrlFilterEnable = true;
     bool m_flowControl = true;
     // Color/Font Changes by ESC Sequences
@@ -386,7 +386,7 @@ private slots:
     bool m_monitorActivity = false;
     bool m_monitorSilence = false;
     bool m_notifiedActivity = false;
-    QTimer* m_monitorTimer;
+    QTimer* m_monitorTimer = nullptr;
     int m_silenceSeconds = 10;
 };