Game settings won't save!

[Arcade-Projects]

I picked up a Rambo for a great price. Super stoked until realizing no settings save. The stokeness turned into sadness

NOTHING saves. Main menu like coin assignments, nor in-game settings. It does not even save if I exit settings into the game without power off -- so I can't even set them every boot up.

Clock DOES keep time after power off.

I found two coin batteries. One on motherboard, the other on the JVS pci board. Replaced both with fresh batteries.

Still no saving.

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