AOF JP AES background sprite issues

I have a jp aof that started producing black or off color sprites in the background layer. It seems to be the most pronounced when there are tiles like the health bar over on top.

I've reflowed all C, S roms as well as the two customs on the CHA board but nothing seems to change so I'm wondering if it's a bad rom, problem is I have no idea which of them it could be.

Other games do not exhibit this issue, for example I can play samsho1 without problem, so i believe it's the cart not a problem between the slot and video chips.

I've also cleaned the game and slot well , a given but worth mentioning for deducing the problem.

Images of issue here
https://imgur.com/a/VJgij1R

I beeped out everything on the CHA board from the cart pins to their initial next point and all seemed to be ok, even those that went to the custom chips (neo-273 and neo-zmc2)

If it is a rom that's the issue I'm not sure how to find out which one contains the sprites/tiles. I used WinKawaks to find the affected areas (see attached) but not sure it helps find where they exist in the C or S rom areas.

I also wanted to rule out the PSU, this console is an original AES - no voltage regulation daughterboard etc.
PSU reads a steady 5.5v
I cleaned up the barrel plug and jack on the console for good measure, same deal.

It's likely a bad C ROM somewhere. Which one, sadly I can't advise how to narrow that down exactly. I guess you could get an emulator that allows you to run a game without a particular ROM file and just go one at a time singling out one C ROM file to exclude until you find the one with the backgrounds affected.

Thanks,
I agree it's either a C rom or the neo-273.
Before I bother shotgunning C roms, I've ordered a replacement neo-273 from furrtek in hopes it will fix. I didn't want to sack a good cart or cha board to do it.

So searching some more, I found this thread which shows my issue.

http://www.neo-geo.com/forums/showt...hes-(vertical-line-syndrome)-NOW-W-PICS/page3

I'm going to attempt adjusting the pot and perhaps look at getting a new psu

Ok this is fixed, it was the orange pot adjustment that took care of it! I guess it was crystal and power related somehow.

Good job on figuring it out, man. I’m guessing that bumped up voltage a little bit perhaps? I get the same sort of issues when running my NeoSD. It’s intermittent, but maybe it’s the same cause and fix. Also, what’s the mod going on around the CXA? Bypass mod?

Thanks man,
Yeah it must have to do with some sort of crystal/power sync or attunement.

As for that mod, its factory from what I can tell as I didnt perform it. You can't really see it but there is a resistor jumped.

Good to hear it was actually an issue with the console. Sorry I wasn't more help.