Hello there!
?
As always happens in electronics repair, the first thing you see, no matter how clear and accurate it may seem, never solves the problem.
That IC hasn't made any improvements to the counter's behavior, so I was wrong. I have to continue investigating. I was pretty sure that the two signals, reference and pulses, coming to this IC are fine. But clearly there is some problem.
Some updates later...
Regards,
Ruben
RubenRubio