Inputmask backspace issue

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  actions: {
  	updateSsn(unmaskedValue, maskedValue){
  		this.set('ssn', maskedValue);
		}
	}
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
<br>


{{one-way-input-mask value=ssn mask='999-99-9999' type="tel" update=(action 'updateSsn')}}

{{ssn}}
<br>

twiddle.json

{
  "version": "0.14.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "1.13.13",
    "ember-template-compiler": "1.13.13",
    "ember-testing": "1.13.13"
  },
  "addons": {
    "ember-inputmask": "0.6.8"
  }
}