Thanks tuftyone,
The thread led me to a resolution indirectly, as the member took his machine to s service department who told him what they did to fix it.
I could'nt go back to an earlier firmware has only have a disc for v1.70, but based on their description I did the following:
1. Factory Reset (Hold STOP while pressing On/Off). Let it power off.
2. Remove mains supply for a few minutes (I allowed 10).
3. Power on recorder - comes up on Easy Set Up.
4. Follow menu to tune digital channels.
5. When completed go to Options menu - Setup/Options
6. Set Auto Software Update OFF
These actions to date have resolved the fault.