How to fix the "all the M-Fi Controllers are all identifying as the same controller" problem on AppleTV apps

I've seen a few people having the same problem, but no one really clearly explained how to fix this.

I own four Nimbus controllers, and recently my controllers stopped working on local multiplayer games. All four controllers would identify as Controller One, and the other three would stop working.

An update in the AppleTV software, or an update in the app itself caused this, but here's how to fix it:

1. Rename the controllers so that each one has a different name. You cannot do this on the AppleTV, currently, so you have to connect the controllers to your iPhone, iPad, or Mac. Once connected to the Bluetooth on your device, click the little blue exclamation mark next to the name of the device on the Bluetooth menu. Then, click on its name, and rename each device.
2. Disconnect the controllers from your device and reconnect them to your AppleTV. AppleTV will recognize the name change the next time you reconnect the controller to the AppleTV's Bluetooth.
3. When you turn on the controllers, each one will still show the same identity, but when you use them in your app, the app will cause them to change designations (controller 2, controller 3, etc).

Enjoy your local multiplayer gaming.