When I activate either the Volume Up button or the Enter/Test button the game responds as if I pushed both buttons simultaneously. I replaced the four button switch and got the same results. I replaced the coin door interface board (A-14102) and got the same results. I grounded pins J205- 8 and J205-9 separately on the MPU and got the same results. The MPU is relatively new, its the Rottendog MPU089. I don't know if the previous owner had a problem with battery leaks. Any ideas on what to try next?