Quoted from BMSPEED:Had the same issue on mine. I was using ninja balls which magnetize quickly on this game. I swapped out to silver jets and also adjusted the white plunger that holds the balls in place inside the coffin by adding washers to lower it slightly (or at least that's how I think I lowered it, lol) It's been a month of games since and I haven't had any problems even on longer duration games.
I took the plunger assembly off and tried several things (washers in various places, etc) and nothing seemed to matter. I resleeved it (even though it felt perfectly smooth) and removed the washer. Rotated the solenoid on its side and reassembled... And it SEEMS fine. Tested several times with the glass off and then played a decent game where I hit all kinds of modes including casket MB under various conditions (all three balls in the casket as well as only one in the casket with the other two being virtual--following electric chair MB I believe). Didn't notice anything strange.
I'm pretty sure the balls I use are getting magnetized FAST which certainly isn't helping but it does seem at least functional now which is the important thing.
Not sure if it was the resleeve, or rotating the coil on its side, or maybe both...but early returns look good.
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