My NBAFB has an issue (would seem to be an WPC95, etc. games though) where anytime a sling switch is activated during game play, the typical test beep is also played. Everything still functions ok, but just annoying on each sling hit. I have done as much troubleshooting as I can, all switches work fine in test mode, went through matrix, checked all diodes, etc. The last test I did was to leave just one sling switch attached to the circuit, but the beep continues. What other direction do I go next?

yes, diodes are ok via meter. I'm not sure when it started as I have made many improvements to the game, but guessing after I replaced the 2 sling coils and 4 sling switches. I disconnected the coils to ensure no interference issues, and verified all the wiring a couple of times to the switches. That is why I also disconnected all the switches and installed one old switch to eliminate the recent changes causing trouble.

Thanks for the suggestion. I have already checked all the switches in test mode, watching the matrix as well to ensure it's only one at a time.

right, odd indeed. Why I posted for more expert eyes on it. Thank you for the help - no hate at all. I'm happy to put the old switches back, and understand this could be a stable, non-issue environment. But I'm not certain that was the "change" point with the beep. Plus if I have one old switch wired back in, and they others out, then I feel like it's doing the same thing, removing all the new switches as a possible problem point.

Another direction I may go is because the sling switch sound during play mode is two tones, something like "high tone, low tone" or "da-dot", I'm thinking I need to figure out where/how that sound is made. Maybe a tilt sound, as it has a negative vibe to it. And let's say it is the tilt, that would mean the tilt switch is firing, which is what the matrix diagnosis would tell me too....

Well, can't find it. Played a few games (fun diversion), even tried all the switches. I think I have it heard it before, but can't place it. It's a negative 2-beep sound, like when you are not allowed to do something in the game.

I think I'm into the matrix now to test all the switches by hand, even the boards, reading lots online, may get a scope if needed.

ok, I did't find any issues so far in testing all diodes and switches in the row/columns with the slings, but not that surprising as all the research on phantom switches shows another switch involved with random things happening. This case is just beeping, which I can't find a similar beeping in the game.

Perhaps the beeping is normal? Can I ask that someone with a Bally WPC95 game, see if their sling switches made a double beep when activated during game play? I have a limited game set, with a modern stern and an AFM Remake only, so can't test that.

Two videos:

1) hitting sling switch in test mode, and normal beep heard.

2) ball hitting same sling switch in play mode (coil disconnected to better hear the two beeps).

Video #1 is testing a switch in the switch menu. Video #2 is game play with the double beeps of different tones. Same switch. But again, if it's normal for the game, then that is good news... And thanks for helping.

yeah, played that one earlier. He's also hitting the flippers at the same time, so hard to hear. I played two other videos, sometimes you can hear it, sometimes not.

See 0:54 in this one, pretty clear you can hear it:

Thanks for all the help. It's certainly possible the sound is made during different modes. Sometimes, when there is other louder stuff happening, I can't tell if it's there or not. Only when it's quieter can I hear it. I'm feeling better that it's looking to be common sound, not just my game. I thought posting in the NBA thread would be an easy test for owners.

It's actually a lot of fun and easy to play with the kids - they are really into basketball. There are times when I want to play Stern Star Wars - hard, fast, very involved game. But NBA is easier, family fun, more enjoyable with a beer. It's not a "top" game overall, but most folks that have played one, have enjoyed it. You get the idea. And I took mine from a below players game condition to 9/10, even swapped in a new playfield.

yes, hope you do too!

Here's another video of the sounds at 1:13 and 1:14,

You can here it twice pretty clearly. I also slow youtube to playback speed of 0.75 - helps out.

ok, last one. At 2:11, there are multiple sling hits with the tones. Three different examples now, so seems like it's common across the game. I should have started down that path first!

Good thought. Appreciate you sticking with me to figure this out. And I learned all about the switch matrix in the process.

yeah, most feedback has been it's just a normal sound in the game. Thank you.