 
 class UserDefaultsEventNotificationPreferences: EventNotificationPreferences {
 	static let notificationAheadIntervalKey = "EventNotificationPreferences.notificationAheadInterval"
-	static let notificationSound = "EventNotificationPreferences.notificationSound"
+	static let notificationSoundKey = "EventNotificationPreferences.notificationSound"
 	static let notificationsEnabledKey = "EventNotificationPreferences.notificationsEnabled"
 	static let instance = UserDefaultsEventNotificationPreferences(userDefaults: UserDefaults.standard)
 

	}

	var notificationSound: NotificationSound {
		return NotificationSound(rawValue: userDefaults.integer(forKey: UserDefaultsEventNotificationPreferences.notificationSound)) ?? NotificationSound.None
	}

	var signal: Signal<(Bool, TimeInterval), NoError> {

		self.userDefaults = userDefaults
		userDefaults.register(defaults: [
			UserDefaultsEventNotificationPreferences.notificationAheadIntervalKey: 60.0 * 60.0,
			UserDefaultsEventNotificationPreferences.notificationSoundKey: NotificationSound.Themed.rawValue,
			UserDefaultsEventNotificationPreferences.notificationsEnabledKey: true
			])
	}
