Weird behavior HP41c

[Neve]

Hi again,

Neither shorting the battery contacts nor the inverted batteries method induce a MEMORY LOSS on this machine. The only thing that does that is the on/clear sequence. Or, of course, removing the Quad Memory module.

Now, I don’t know if this is gonna help since this behavior doesn’t happen all the time.
It’s pretty sporadic and unexpected, and of course very annoying.

PS-1: I used almost totally drained inverted batteries (0.300v each approx).
PS-2:This machine doesn’t suffer from broken posts. The logic board is held in place by hex nuts that I have never removed.