Sometimes during a game of AFM I'll get a "return to battle, soldier!" notice and another ball will get kicked onto the playfield. If I let one of the balls drain I can keep playing. I did the basics by reseating the ball trough cables and cleaning the optos.
Haven't been able to find answers because I don't know what to search for (looking for "ejects extra balls" or whatever returns results for how to get an extra ball award).
Thanks!