Android : App hangs on clicking the notification

Below is my code for showing a Notification, and after clicking it I redirect to another activity using the PendingIntent

But when I click on this notification my application hangs;

On checking my LogCat I see continues GC invoke logs

Please correct where am i going wrong:

private void showNotification(int notifyId, String alertMsg, PendingIntent intent) {
    Uri soundUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);

    mNotificationManager = (NotificationManager)
            this.getSystemService(Context.NOTIFICATION_SERVICE);
    NotificationCompat.Builder mBuilder =
            new NotificationCompat.Builder(this)
                    .setSmallIcon(R.drawable.ic_launcher)
                    .setContentTitle(getResources().getString(R.string.app_name))
                    .setStyle(new NotificationCompat.BigTextStyle().bigText(alertMsg))
                    .setSound(soundUri)
                    .setContentText(alertMsg);
    mBuilder.setAutoCancel(true);
    mBuilder.setContentIntent(intent);
    mNotificationManager.notify(notifyId, mBuilder.build());
}

ALSO ABOVE CODE DOES PLAYS THE DEFAULT NOTIFICATION SOUND.

Please help.

Thanks in advance.