Strange behaviour of a Seiko O574, help needed

[elceedee]

Im sitting here with my brothers O574 in my hands. Its NOS, so before disassembling/opening/testing it im asking some advise.

The watch is fully functional with a new battery but is acting in a way i havent seen yet; its switching from the 6th minute to the 9th minute (03.26 to 03.29 , 04.26 to 04.29 etc etc), also behaving like this when setting time.
It seems to be something with the pcb/chip.

Did anyone came across this? Any tips/tricks?

Thanks in advance.

[elceedee]

I guess this is really weird Seiko behaviour hmm ?

[dutchsiberia]

Very weird. I had a Seiko that counted from 1 to 9 and then to 1 again. Unusable.

[Kasper]

i have a nos citizen with jumping digits...i think it's a problem with the processor...impossible to repair..tried everything.

[elceedee]

I more or less concluded the behaviour is caused by a defective chip, after reading your messages im affraid this will be the final conclusion.. Thanks for the help guys!

By the way, its a NOS Seiko O674-5009. We will look out for replacement parts.