Yeah it's necessary, we don't currently create a new Radio, but we probably could... something like one of the following:

```js
beforeEach(function() {
  this.Radio = clone(Backbone.Radio);
});
// or...
var originalRadio = Backbone.Radio;
beforeEach(function() {
  Backbone.Radio = clone(originalRadio);
});
```

We probably need to make it a [deep clone](https://www.npmjs.org/package/clone).