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[SOLVED] MVS one slot audio dropping out

kikaso

kikaso

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So I’ve had two Metal Slug MVS carts pass through my collection that have the same audio glitch; after about 15-20 minutes of letting the game loop through the attract mode, the audio cuts out. Even if I insert credit and play game, the audio doesn’t come back unless I cycle power off and on.

Has anyone else had this issue? Is this a known glitch?

EDIT: Running game on a MV1FZ in a JAMMA cabinet and also HAS supergun. Other games work fine.
 
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I can say with some confidence that the cartridge isn’t the problem because I’ve had this issue on two different MVS carts now and it’s also an issue on the TerraOnion multi running Metal Slug ROM.

I’m thinking now that it may be my single slot motherboard but this is the only cartridge exhibiting sound issues. I’ve tested five other MVS carts and none of them have this audio issue.

Thoughts?
 
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Clear the MV1FZ's backup ram by going to the hardware test, flipping through with start, and then pressing ABC together on the screen asking about clearing it.

Also, clean the games and cartridge slot with contact cleaner, like Deoxit D5.
 
Thanks for the response. I’ll try clearing the backup ram but I’ve already cleaned the edge. Very odd that this seems to happen with the TO multi cart as well
 
Sounds like a good plan. For what it's worth, usually distilled water or IPA looks like it does a fine job cleaning, but I've found that for really stubborn old systems and hardware, there's nothing like real contact cleaner to get everything working 100% on the first try.
 
Neo-Alec said:
Sounds like a good plan. For what it's worth, usually distilled water or IPA looks like it does a fine job cleaning, but I've found that for really stubborn old systems and hardware, there's nothing like real contact cleaner to get everything working 100% on the first try.
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I cleaned the edge connector and reset the backup ram but audio still dropped out after about 25 minutes.

Given that it’s only happening on Metal Slug 1, (three versions including multi cart running rom file) I’m being led to believe that it could be my single slot motherboard. That still doesn’t make sense to me because I’ve now tested several MVS carts and Metal Slug 1 is the only one having this issue with the audio. Two Metal Slug carts and a rom cart. So bizarre.
 
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Could be the power supply needs to be upped slightly.
 
Tried that.

What's odd is that if I insert a credit right away and play through the game, the audio is fine. The audio only drops out if left in attract mode for 20 minutes or more.
 
For what it's worth, I tested out my Metal Slug Cart in a MV1FS last night. After 25 minutes, the attract sound was still audible. I tested both the JAMMA mono audio and stereo audio over the headphones connection (test ran twice, over 25 minutes each time). The power was reading 5.0v on the HAS supergun.

It's not an apples to apples comparison to your setup, but hopefully this helps.
 
meybarra said:
For what it's worth, I tested out my Metal Slug Cart in a MV1FS last night. After 25 minutes, the attract sound was still audible. I tested both the JAMMA mono audio and stereo audio over the headphones connection (test ran twice, over 25 minutes each time). The power was reading 5.0v on the HAS supergun.

It's not an apples to apples comparison to your setup, but hopefully this helps.
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That is helpful! Thanks for running the tests on your end.

I only have the one MVS motherboard and while this is the only game having issues, I’m thinking it might be the mobo.
 
Could the Nazca driver stress a specific part of Z80 / YM2610 / RAM that got weaker over time ? Maybe try other Nazca games like Neo Turf Masters (Since later Nazca got absorbed by SNK and mayve the driver changed after)
 
Ryoandr said:
Could the Nazca driver stress a specific part of Z80 / YM2610 / RAM that got weaker over time ? Maybe try other Nazca games like Neo Turf Masters (Since later Nazca got absorbed by SNK and mayve the driver changed after)
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So the audio dropped on Neo Turf Masters just as you predicted. I don’t have an original cart but it dropped on a ROM cart just like Metal Slug 1.

So sound CPU or RAM is bad you think?
 
Oh wow, that's quite the confirmation !
While Z80 and RAM are common failures, the fact that other games work and Nazca ones fail, it makes me think YM2610 is at fault because maybe FM and SSG portions are more used ; games tend to pretty much use only PCM part. 2610 also runs hot by default. It is a pain to change tho if you don't have a proper desolder gun.
Maybe try Magician Lord if you can, I know it uses a decent amount of FM.
 
I’ll test Magician Lord tonight.

I’ve desoldered these kinds of chips before. Definitely a pain but I have confidence I can get it out safely if I have to 😅

Thanks again for the help. I’ll update the thread with what I find.
 
Recap the Mobo..
when things stop working after a period of time like this it's usually due to heat soak... Caps are especially suseptable to this and naturally break down over time, plus they're cheap an easy to replace.

it's entirely possible that it's Z80, but I'd start with the caps since there's no real harm in recapping.

You can also feel around the circuit to see if any chips are getting hot and try piggy backing them to see if that resolves the issue.
 
twistedsymphony said:
Recap the Mobo..
when things stop working after a period of time like this it's usually due to heat soak... Caps are especially suseptable to this and naturally break down over time, plus they're cheap an easy to replace.

it's entirely possible that it's Z80, but I'd start with the caps since there's no real harm in recapping.

You can also feel around the circuit to see if any chips are getting hot and try piggy backing them to see if that resolves the issue.
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Thanks for the advice. Unfortunately, (or fortunately?) the board has been recapped. That four layer board was a pain!

ekorz said:
http://smkdan.eludevisibility.org/neo/diag/ if you can swap the bios and load up the m1 onto a multi-cart
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I can totally swap the bios but need to find someone to burn it for me. This is helpful thanks!
 
Ryoandr said:
Maybe try Magician Lord if you can, I know it uses a decent amount of FM.
Click to expand...
Yep, lost audio after about 20 mins. I’ll try the diagnostic bios @ekorz recommended and report back. Updated thread title to reflect the fact that more games are dropping audio.
 
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