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I picked up this board recently in need of repair and I'm out of ideas. It "works" (plays all music and sound fx) but you have to have the volume cranked all the way up in order to hear anything. When I got it, it had the original caps which leaked causing some trace damage and no fx, mostly around the oki chip. Here's what I've done so far to troubleshoot:
▪FULL cap kit (ignore the original axials in the pic, they've since been changed)
▪replaced main amp (appears to be working fine, is barely warm to the touch as it should be) and all 3 op amps
▪fixed all broken traces I could find (4 so far)
▪replaced the oki chip (this restored all sound fx)
▪swapped all socketed chips marked with an "X" in the pic with one's from a working board
Screenshot_20250706-013018_Facebook~2.jpg
▪tried 3 different known working volume pots
▪tried 2 different known working ribbon cables (yes they were plugged in the right way)

Are there any other components that could possibly cause this volume issue that I missed in my troubleshooting? Could it possibly be a resistor out of tolerance/open or a bad cap (one of the little yellow ones that are all over the board), or yet another bad trace that I missed?
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