Hi Tom – Helen, Jide and I all live next door to each other and have been having intermittent but recurring issues on this for a while.
It seems to happen when we have very cold weather overnight (don't laugh but it seems to be the case) and then it corrects later in the day. The three systems all tend to go off around the same time but not necessarily at the same time and then return separately.
Helen has had the engineer out (Alan who looks after the communal system) twice and he cannot find any faults but hasn't been here when the problem has been in play. We had it again over the weekend (Sat and Sun) for a while on both days but it corrected.
Not much help for you I know – and I am unsure what the solution is until Alan happens to be here when the problem is in play.
It does seem to correct itself, but I tend to go through the motions of various steps just to see if it fixes.
1. Soft reset by turning off at wall for 20 seconds. Turn on. Leave 4 minutes. Hit the 'Sky' button on the remote.
2. Software update (turn off at all, hold down the 'back up' button on the box NOT the control and then turn back on at plug – keep holding the 'back up' button for about 20 seconds and the software update kicks in).
3. Planner rebuild (go to Services, hit '0' then '1' then 'enter', on the new menu go to Planner Rebuild).
With all of these, I get the 'no signal' or 'system initialising' sometimes for 20 minutes before it works (if it does).