However, When I press the orange "warn" badge, nothing happens.
Is anyone able to tell me how to track what device / app is causing this?
I did reboot the hub this morning, however no joy.
The next platform update, currently in beta testing, will tell you if there's a matching device on the hub.
You still probably won't be able to do anything about it if it's just the device asking the hub for a firmware update on its own (rather than you doing an update), as it normally is when you see this.