Vegas board audio problem

Paladin

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Testing a Vegas boardset currently running War Final Assault, the left audio channel is messed up. I've tried pulling it off the JAMMA connector (amped on the boardset) and off the line out pins (amped by my cabinet). The sound is the same either way. I've also run it with Dark Legacy ROMS and drive with the same issue.

Does anyone have an idea what might cause this? Someone who looked at my board noted that a crystal on the board has an odd discoloration, and suggested swapping it. I thought I'd post it here first to see if anyone has had this issue.

I've got left and right swapped in the video, but I swapped the cables around so it's correct now.
 
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Small update, swapped the crystal out with no change. No idea where to look next.

Looking at the board for audio components that have 2 of the same part that might explain one channel being good and the other bad, I see two surface mount TL084's (actually ST 084C) in the sound area. If one goes bad could it introduce static? I've never messed with surface mount and don't really want to if it isn't likely the problem.

Taken from Pinside pinball forum:
Problem sound boards can produce a large amount of static. The TL084 quad Op-Amp (U7 & U8 on WPC, U21 & U29 on WPC-DCS, U1 & U2 on WPC-95) can be the cause of this.
 
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Replaced what I'm pretty sure is the 'left' TL084. My first go at surface mount and although it isn't exactly pretty, all the pins are in contact with the pads and none are shorted together. Unfortunately it didn't fix the issue, although it did change it slightly.

Now the left/right speaker test still has a perfect 'right', but the 'left' is much quieter. It still has the static in it but the volume is much lower. The bad change is that there's now a crap ton of hum from the left side all the time. The hum changes with HD access as well.

Another thing I noted is that the attract sounds are seemingly only coming from the left channel, with the loud hum and static like they are over driven. When I hit the coin switch I get a nice clear coin drop sound from the right channel.

I think I'm done with this board. I had bought a couple untested boardsets with one video card with the thought of selling the second set to reduce the cost of the one I'm keeping. I've dumped enough time and money into trying to get the second one running that I'd still be in the hole if I did fix it.

Pretty cool that the video card I bought was a cheap retail Voodoo 2, not an 'official' one. War seems OK with it but if I remember correctly when I put Dark Legacy EPROMS in it just booted to the test menu with a 'test switch stuck' error. I was going to look into it after getting the sound fixed but don't care at this point. I guess I could swap it into the other working set to see what happens..
 
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