No sound from remote notification - notifications

Question

Could some one help me to understand why i'm not receiving sound from remote notifications in IOS 10 Swift 3.
Here is my code:
AppDelegate:
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey : Any]?) -> Bool {
let settings = UNUserNotificationCenter.current()
settings.requestAuthorization(options: [.badge, .alert, .sound]) {(granted, error) in
}
return true
}
// Override point for customization after application launch.
func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable : Any]) {
let viewController = self.window?.rootViewController as! LoadingCloudDataViewController
let notification: CKNotification = CKNotification(fromRemoteNotificationDictionary: userInfo as! [String: NSObject])
if(notification.notificationType == CKNotificationType.query) {
let queryNotification = notification as! CKQueryNotification
let recordID = queryNotification.recordID
viewController.fetchRecord(recordID: recordID!)
}
}
And here is the notification subscription code:
func subscriptionNotificationsKcal() {
publicDatabase = container.publicCloudDatabase
let predicate = NSPredicate(format: "TRUEPREDICATE")
let subscription = CKQuerySubscription(recordType: "Kcal", predicate: predicate, options: .firesOnRecordCreation)
let notificationInfo = CKNotificationInfo()
notificationInfo.alertBody = "New Calories Item was Added"
notificationInfo.shouldBadge = true
subscription.notificationInfo = notificationInfo
publicDatabase?.save(subscription, completionHandler: ({returnRecord, error in
if let err = error {
print("subscription failed %#", err.localizedDescription)
}else{
print("sub success")
}
}))
}

Answer 1

By default the sound is muted. To activate it, in the case of this example, use the following code:
notificattionInfo.soundName = "default"