Datel controller with your Xbox 360 all of a sudden? Well, you can blame yesterday's stealthy system update, which has wreaked havoc with some wireless controllers – specifically, the TurboFire 2, WildFire 2, EVO line and the Super Sports 3X steering wheel peripheral.
Right now, there is a fix, but it's complicated. You'll have to download a software update made specifically for your hardware, which you can find here. Microsoft doesn't officially support your Datel controller, after all – and it's not like the two are best pals.