Raymarine ST50 unlock code problem.

[Teddy]

I have Autohelm (Raymarine) ST50 plus GPS, Speed, Depth and Tridata repeater, all linked using the SeaTalk bus. The GPS is set as master, and the security code feature has been switched off for over 3yrs. Now all of a sudden the depth and speed are asking for the unlock code, although the GPS is working normally. Naturally I can't find the code, and anyway, why has it changed by itself. The unit has not been fiddled with because it happened overnight (on board).
Has anybody come across this problem, or any useful suggestions? I have looked the Raymarine website to no avail. Thanks.

 

[peasea]

Call Raymarine - I run ST50 units and have found Raymaine most helpful.