- Resynch Wiimote from System menu + red button on console + red button on Wiimote.
Try launching USBLoader. If wiimote desynch again, then:
- Resynch on system menu, like above.
- Reinstall cIOS.
Also, I noticed that booting the console from wiimote's power button has some effect on Priiloader and Wiimote synch.
- Don't boot the Wii with the Wiimote's power button, but use the console's Power button.