Williams Black Knight (Williams, 1980) missing digits

[bkwillslayyou]

hi everyone, i have been working on my black knight for 6 months with mpu repairs. i have the game booting into attract now, but i am missing the first 2 digits on all four of the player displays, when i do the display test, all the digits are there and all displays work correctly. this game has a new display pia and all new roms. any ideas where to look would be greatly appreciated

 

[spalmer]

Bad 74154 chips on the MPU board can cause strange behavior.