I picked up a Space Station yesterday with some seriously possessed sound issues....When you start a game it starts to play the regular main theme for about 2 seconds, and then shifts to the multiball music for the entire time. Many sound effects are incorrect and overlap sometimes causing weird digital crap and distortion....however all the voices are there and are correct. At the end of the game it plays what should be the "normal" main theme as the end of game music and then has a bunch of garbled digital crap when it fades out and ends for about 5 seconds.....THEN (this is the REALLY weird crap) when in attract mode, after the attract sound is played the main theme will start playing super faintly (gotta put your ear on the speaker to hear it) non stop until a game is started. PLUS...when you go into sound test mode (during all and any tests, even switch test and display test) the "normal" main theme plays constantly...BUT....when you go to sound test and go to "main theme" it plays the multi ball theme again, just like when in game play.

The MPU has some very light acid damage on the two PIA chips below the holder and to the area to the right of those chips...I "neutralized" it for now and cleaned it up...i'll verify continuity tonite. That will all get replaced in time, parts are on order. I reseated all the sound chips, and threw on a new ribbon cable i had on hand. Other then the super light acid damage, all the boards match are super clean and hack free.

The game plays perfectly fine too. And the displays all read correctly.

Any thoughts/suggestions? I know system 11 really well...I've just never run into this specific issue, and i'm trying not to instantly assume it's the PIAs on the MPU....should I?

Thanks!

Thanks! Everything "seems" ok...u51, specifically the left side, is pretty warm even during attract mode, and U8 on the sound board is very hot...also in attract mode.

Ok....with everything unplugged from the sound board except power (J3) U8 is still super hot, too hot to touch almost.

Thanks...here ya go....the back is clean as a whistle as is the rest of the board...

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Thanks! The wrong music is played in test mode...and many times the sound board will lock up...but it only locks up during test mode.

I agree on the corrosion, it's very very light...and there is none on the actual battery holder which is very odd.

I'm taking both boards to a buddy of mine's house tonight and gonna swap them into his earthshaker and see how it performs in there.

Also I verified continuity last night through that whole area and everything checks out good.

Can a bad sound ROM on the soundboard because these issues?

Thanks! I didn't realize that's how these work, but that makes allot of sense! I wish I could post the short vids I shared on the Facebook groups on here. It would help allot I think.

Thanks! Unfortunately I already tried a brand new ribbon cable I had...after I get back from my buddies house tonite where I'm gonna test both boards in his earthshaker, I think I'll have a better handle on things, or at least have it narrowed down to one board.

Problem solved! It was a bad trace from pin 12 of u42 to the SCR. Apparently I missed it when I did my continuity check. Soldered a jumper onto the back and all is well with the world again. Thanks for all the help!!!

So interesting update....everything is still working great BUT.....if i go into settings and turn off the attract sounds, when my game is over it plays the end of game song forever until i start a new game or cycle power. BUT....if i turn the attract sounds to anything other then off (Allot or Less), everything fades out as it should at the end of the game.

What's even more interesting is, when everything was all messed up sound wise, before i found that bad trace, this didn't happen. I recheck'ed my jumper job, and i for sure didn't solder bridge anything when installing it.

I know...i am...parts are on order. I'm just curious if anyone has seen this issue before so i can look other places too in the event that replacing the damaged areas doesn't help.