Discussion about the Korg PolySix synthesizer

I have strange RAM problem. I've doubled memory. Added second 5514, soldered pin to pin except pin 8. connected 10k from pin 18 to pin 8 in both ic's. also destroyed connection between ram and ic25.

and now the best thing. ram switch works :) but. in all banks on second chip sounds are dubling i mean: 1 is same like 5, 2 same like 6, 3 same like 7, 4 same like 8 in all banks [a-d].

what's the problem?

ps. sounds in ram chip that is factory soldered works just fine!