BH-423, no sort function

[Synthohol]

just to be sure i understand, there is no finisher right?
you can only do criss-cross sort having portrait paper in one tray and landscape in another.
no offset sort with no finisher.

you said paper settings were right but you didnt mention orientation.

[Hansoon]

BH-423, no sort function (No finisher, just the machine)
This machine came long ago from a wholesaler. The mechanical counter was at 150.00, but the electronic counter 000.000. So obviously something weird with the NVRAM. Those days, we explained to the customer the situation, and he accepted to take the machine as it is.

However, after 1.5 years he wants to use the sort function, and it worked from time to time, but not always. Now suddenly, strange enough, no sorting anymore at all. The function is visible and highlighted in the display, and it can be chosen, but sorting does not function. Paper and other settings are right. I checked it several times. Reinstalling firmware worked for a few days, but then the problem came back and sorting is not working anymore at all.

I have a donor machine and could replace the boards with their own NVRAM belonging to it (counter settings are not important, and I have the feeling that the original NVRAM is the culprit). Since it is a very unpleasant job to do, with a clear risk, I would love to avoid replacing the boards. Any ideas for an alternative, please?

Hans