Hi Alan,
My name is Tom by the way, and i live in Gateshead. Unfortunately, i cannot remember my password to change the settings...old age i suppose.
I have cleaned the R1 relays and cleaned S1 and S2 on the search unit. The latchbar is rather 'hot', but is not binding in anyway.
The problem seems to be intermittent, sometimes the keys reset and sometimes they don't.
The latchbar is that hot I cannot keep my fingers on it without them burning!