diff --git a/src/v4l2sinkproperties.cpp b/src/v4l2sinkproperties.cpp
index 22f334e..d03f64f 100644
--- a/src/v4l2sinkproperties.cpp
+++ b/src/v4l2sinkproperties.cpp
@@ -44,6 +44,7 @@ V4l2sinkProperties::V4l2sinkProperties(QWidget *parent) :
 	ui->comboBox_format->addItem(V4L2SINK_RGB32, V4L2SINK_RGB32);
 	ui->comboBox_format->setCurrentIndex(
 		ui->comboBox_format->findText(format));
+	connect(ui->comboBox_format, SIGNAL(currentIndexChanged(int)), this, SLOT(onComboChanged()));
 
 	ui->label_warning->setStyleSheet("QLabel { color : red; }");
 	enableStart(true);
@@ -99,6 +100,11 @@ void V4l2sinkProperties::onStop()
 	v4l2sink_disable();
 }
 
+void V4l2sinkProperties::onComboChanged ()
+{
+	setWarningText("");
+}
+
 void V4l2sinkProperties::enableStart(bool enable)
 {
 	ui->pushButton_start->setEnabled(enable);
diff --git a/src/v4l2sinkproperties.h b/src/v4l2sinkproperties.h
index 5c8dab4..34c96e6 100644
--- a/src/v4l2sinkproperties.h
+++ b/src/v4l2sinkproperties.h
@@ -44,6 +44,7 @@ class V4l2sinkProperties : public QDialog
 private Q_SLOTS:
 	void onStart();
 	void onStop();
+	void onComboChanged();
 
 private:
 	Ui::V4l2sinkProperties *ui;