The "e" segment on the master display board and players 1 & 2 quit working. I traced the problem to the displays. Ended up being a short in display 1 somewhere - if I unplugged display 1 the "e" segments were not missing on player 2 and master display. If I moved display 1 to any other players the issues with missing segments on other displays appeared.
My question is why would a short in one display affect other displays - in this case short in display 1 that also affects display 2 and master?