diff --git a/translator.go b/translator.go
index bfa77d9..18a4fc0 100644
--- a/translator.go
+++ b/translator.go
@@ -17,19 +17,45 @@ const (
 	soundURL = "https://translate.google.com.vn/translate_tts?ie=UTF-8&q=%s&tl=%s&client=tw-ob"
 )
 
+type Lock struct {
+	stop        bool
+	threadCount int8
+}
+
+func NewLock() *Lock {
+	return &Lock{
+		stop:        true,
+		threadCount: 0,
+	}
+}
+
+func (l *Lock) Available() bool {
+	return l.stop && l.threadCount == 0
+}
+
+func (l *Lock) Acquire() {
+	l.stop = false
+	l.threadCount++
+}
+
+func (l *Lock) Release() {
+	l.stop = true
+	l.threadCount--
+}
+
 type Translator struct {
 	srcLang   string
 	dstLang   string
 	soundLock *Lock
 }
 
-func NewTranslator() Translator {
-	return Translator{
+func NewTranslator() *Translator {
+	return &Translator{
 		soundLock: NewLock(),
 	}
 }
 
-func (t Translator) Translate(message string) (string, error) {
+func (t *Translator) Translate(message string) (string, error) {
 	var data []interface{}
 	var translated string
 
@@ -63,7 +89,7 @@ func (t Translator) Translate(message string) (string, error) {
 	return "", errors.New("Translation not found")
 }
 
-func (t Translator) PlaySound(lang string, message string) error {
+func (t *Translator) PlaySound(lang string, message string) error {
 	url_str := fmt.Sprintf(
 		soundURL,
 		url.QueryEscape(message),
@@ -71,25 +97,35 @@ func (t Translator) PlaySound(lang string, message string) error {
 	)
 	res, err := http.Get(url_str)
 	if err != nil {
+		t.soundLock.Release()
 		return err
 	}
 	decoder, err := mp3.NewDecoder(res.Body)
 	if err != nil {
+		t.soundLock.Release()
 		return err
 	}
 	otoCtx, readyChan, err := oto.NewContext(decoder.SampleRate(), 2, 2)
 	if err != nil {
+		t.soundLock.Release()
 		return err
 	}
 	<-readyChan
 	player := otoCtx.NewPlayer(decoder)
 	player.Play()
 	for player.IsPlaying() {
-		time.Sleep(time.Second)
+		if t.soundLock.stop {
+			t.soundLock.Release()
+			return nil
+		} else {
+			time.Sleep(time.Millisecond)
+		}
 	}
 	if err = player.Close(); err != nil {
+		t.soundLock.Release()
 		return err
 	}
 
+	t.soundLock.Release()
 	return nil
 }
diff --git a/ui.go b/ui.go
index 3d2a1e6..4fa1c3e 100644
--- a/ui.go
+++ b/ui.go
@@ -134,21 +134,37 @@ func translatePageHandler(event *tcell.EventKey) *tcell.EventKey {
 		}
 		dst_box.SetText(src_text)
 	case tcell.KeyCtrlO:
-		message := src_box.GetText()
-		if len(message) > 0 {
-			err := translator.PlaySound(translator.srcLang, message)
-			if err != nil {
-				src_box.SetText(err.Error(), true)
+		// play source sound
+		if translator.soundLock.Available() {
+			message := src_box.GetText()
+			if len(message) > 0 {
+				translator.soundLock.Acquire()
+				go func() {
+					err := translator.PlaySound(translator.srcLang, message)
+					if err != nil {
+						src_box.SetText(err.Error(), true)
+					}
+				}()
 			}
+
 		}
 	case tcell.KeyCtrlP:
-		message := dst_box.GetText(false)
-		if len(message) > 0 {
-			err := translator.PlaySound(translator.dstLang, message)
-			if err != nil {
-				dst_box.SetText(err.Error())
+		// play destination sound
+		if translator.soundLock.Available() {
+			message := dst_box.GetText(false)
+			if len(message) > 0 {
+				translator.soundLock.Acquire()
+				go func() {
+					err := translator.PlaySound(translator.dstLang, message)
+					if err != nil {
+						dst_box.SetText(err.Error())
+					}
+				}()
 			}
 		}
+	case tcell.KeyCtrlX:
+		// stop play sound
+		translator.soundLock.stop = true
 	}
 
 	return event
diff --git a/utils.go b/utils.go
index 94aa536..884e4fc 100644
--- a/utils.go
+++ b/utils.go
@@ -13,24 +13,3 @@ func SetTermTitle(title string) {
 	print("\033]0;", title, "\007")
 }
 
-type Lock struct {
-	stop        bool
-	threadCount int8
-}
-
-func NewLock() *Lock {
-	return &Lock{
-		stop:        true,
-		threadCount: 0,
-	}
-}
-
-func (l *Lock) Aquire() {
-	l.stop = false
-	l.threadCount++
-}
-
-func (l *Lock) Release() {
-	l.stop = true
-	l.threadCount--
-}