Indeed, the controller of a mp4001 was sometimes ok, and sometimes not ok.
It kept getting worse in time...
So it starts failing once a week and gradully became worse to 3 times a day, going offline.
When user toolls are accessed when the mp4000 was offline, only the "counter" is shown solid black, all the rest is gray.
So, from that point we knew it was the controller.
So, an electronic board can work sometimes good, and sometimes bad.
That is not good news; it makes trouibleshooting far more difficult!
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