Many times when multiball starts, the trough kicker coil fires but the ball is not kicked out. After 3 or 4 attempts it stops trying. I have removed the apron and checked for obstructions, replaced the coil sleeve and checked the diodes but still have the problem. Also, I noticed many times the outhole kicker does not fire and all the balls pile up below the flippers. When I perform the solenoids self test I do periodically get the same issue.