I had the same problem with another manufacturer's receiver. I had disconnected it for a year, moved house and reconnected it. After updating, the channel numbers were scrambled. I contacted the manufacturer, who said that they had sent an update over the airwaves, which would have cured this and I had missed it, but they did not support their digiboxes any more and would not be sending out the update again. They refused to offer any other solution, other than buying a new digital recorder unit (for over £150) so I bought another digibox at a car boot sale and threw the scrambled one away.
Adrian Hanwell, October 2013