hey first time post did some searching couldn't find anything to help me yet. I bought this machine not working put new power supply and prom piggyback board on and got machine working almost 100%. Only issue i have now is some sounds are so low you almost cant hear them, other sounds are at normal volume. what I've done some far to fix sound issue is replaced the yrom1 yrom2 drom1 on the sound board. Also check edge connector and solder joints still no change. Any help would be appreciated.