Internal Rabbit 3000 real-time clock does not keep time even if battery powered

We have been using P/N 20-101-0520 (Rabbit RCM3200) in our products for several years

In the last weeks/months, we started to have issues with the RTC not keeping time between power ON/OFF even with brand new batteries to power the VBAT_EXT pin.

VRAM pin is not connected in our design

What could explain this behaviour ?

Please run the following samples and let me know fi you are still seeing this issue:
setrtckb.c
rtc_test.c

How many units are having this issue?

Thanks, I will try these when the unit will be available.

2-3 units are affected, but the latest showed this morning an unreliable battery holder. The others might also have marginal battery holder that were not diagnosed as such.

If you determine the battery holder is faulty, we should bring them in and take a look. I would also want to alert our quality team.