CS2002

Check cables all connected and maybe reboot your hub.

Are you getting the same error on both boxes as it usually only affects one?  If it's both boxes then have you used the /check-services/ function to check for problems in your area? You can also a run a test on your equipment from there. 

If nothing is showing  you could also try the automated Service Status number  0800 561 0061.  This is generally  better  as it gives details of more local issues down to postcode level.

CS2002 is a channel failed error, and the usual advice is to check your cabling, especially that the white coaxial is secure and free from any kinks, and the small connector cable that goes into the back of the 360 which can be very pliable. If you are using an ethernet cable then make sure that it is snug and tight, also reboot both the 360 and hub  at the same time so they can make the handshake again.

When a 360 reboots, it requests an IP address from the hub. So it's best to reboot the hub first as this establishes a network connection and puts it in a position to serve the IP address.

If you are rebooting a TV as well, then do this before the 360 as this ensures that the TV's EDID is ready to be read when the 360 initiates the HDMI handshake.