[SOLVED]Mortal Kombat 2 sound issue.

[gargamel]

Hi

i recently got a MK2 pcb but have some issue with the sound.

When i power on the game, i have one "dong"(Which indicates the games is working properly ?).The rom check screen complete successfully, without no bad checksum.
When i start a 1P game, i have sound but sound disappears. If enters the setting menu of the game, it reappears, but dispparears too. once i exit the game, sound reappears, but disappears again....

the red LED are lighten up on both main PCB and sound board. tried the board on two cabs (mini cute which have same PSU)but same problem..
Game revision is 3.1 (challenger/ immortal edition hack), and board is in good shape..

Any advice are welcome..(not enough juice or too weak psu?)
Killer instinct 1, 2 and UMK3 work perfectly on those PSU

[yosai]

Have you set the sound volume in the test menu?

[gargamel]

yes, i can change and hear the sound in the menu.

[Rossyra]

-5v connected?

[thechop]

If UMK3 works fine in it then this should too tbh as that needs -5 for the sound, quite a high -5 from my experience.Not just fading in and out of the left and right speakers is it, like a stereo/mono issue?Umk3 in my mini-cute is in mono i'm assuming and sometimes the voices seem to fade, for instance when Scorpion says 'get over here' it seems to fade out and you only hear 'get ov..' like it goes from left to right in stereo but its only mono

[paulcan69]

I had exactly the same trouble with my MK2 sound board.
It reported everything ok but in the end I swapped it with another known good board and that cured it.
Hope yours is ok, but just to let you know don't trust those sound tests in the service menu

[gargamel]

If UMK3 works fine in it then this should too tbh as that needs -5 for the sound, quite a high -5 from my experience.Not just fading in and out of the left and right speakers is it, like a stereo/mono issue?Umk3 in my mini-cute is in mono i'm assuming and sometimes the voices seem to fade, for instance when Scorpion says 'get over here' it seems to fade out and you only hear 'get ov..' like it goes from left to right in stereo but its only mono

the sound mute completely after few seconds. doesn t like a stereo/mono issue.

[channelmaniac]

Sounds like bad caps in the audio section.

[gargamel]

Should i try to replace cap on sound board? or main pcb and sound board?

[skykid]

Shoot, I had this exact same problem when I first got my MK2. There's probably nothing wrong with your board at all - there was nothing wrong with mine. I'm racking my brains to remember the fix.

I seem to remember there was a set of wires with a connector on the board that needs to cross over and connect to to some pins on the edge (I'm at work at the moment so I'm going from my poor memory.)

I'll do a search for some old threads and see if I can find out what I did to fix it. In the meantime don't go replacing any boards or anything, there's a good chance it's all fine!

Back in a bit.

[gargamel]

Thank you skykid

[skykid]

Thank you skykid

Ah you're still around, cool.

Okay, I went searching on J+ for my old help request thread - I'm almost 100% sure it was on there (even though I bought it on AO), but alas, I can't find it.

So, looking at my board, there are freaking wires running all over the place. You should have one parallel cable connected to the sound board (the top one) where is says 'parallel', with the other end connected to P12 at the side opposite the Jamma edge connector.

The other should be what I'm guessing is a speaker connector.
One end should also be attached to the same sound board, right on the left of the big capacitor by the heat sink (it's noted as 'PWR/SPKR'), and the other should go to the main board just to the left of the Jamma edge connector in a port labelled P3.

If I disconnect the above mentioned lead: no sound.

The chances are you have all of these plugged in already, as you're getting intermittent sound right? To be honest, the folks here are way more knowledgeable than I, so there may indeed be a possibility that the fault you're having is different to mine (I have heard that the sound on MK2 boards can be finicky.)
Could be a cap replacement issue (don't failing capacitors not carrying charge affect sound like this?), but I think the advice of finding a new sound board is probably going to help. Problem is finding one!

I don't know if any of the above helps at all and sorry I couldn't help any further - without being able to dig up that old thread I'm a little stuck.

hopefully you'll get it all up and running soon Gargamel!

[gargamel]

Hi skykid,

both parallel cable, and power/spkr cable were connected properly. i give a try to your advice once my board is back.

i brought my board to an arcade repair specialist(he will check it for free) i m waiting for the diagnostic result.
once i got my board back, i will post the problem cause and solution (if there is a solution)

[yosai]

Just been having a crack at UMK3 in my E2.

The sound appears to be on full volume in the test menu and the volume adjust (as set in the options) only comes in to effect as the game boots.

Are you sure you have the volume set to an audible level? It would explain this.

When i power on the game, i have one "dong"(Which indicates the games is working properly ?).The rom check screen complete successfully, without no bad checksum.
When i start a 1P game, i have sound but sound disappears. If enters the setting menu of the game, it reappears, but dispparears too. once i exit the game, sound reappears, but disappears again....

[gargamel]

Hi

Yes, i checked that too.

As i told before.

the sound works flawlessly for few seconds and disappear completely.
entering the setting menu make it come back, but when leaving the setting menu then start a game, it will disappear after few seconds.
i hope to have news tommorrow from the repair shop.

[gargamel]

Problem was bad cap on sound board...