MV-1FZS No sound

This MVS has a torched 12V line, so I don't plan on restoring audio to the JAMMA edge. Rather, I am trying to pull stereo sound from it. I've done the 5V modification as outlined on the Jamma Nation X tutorial. However, I hear no audio except for some buzz and very faint PSG audio.

I checked that the YM3016 (the DAC) and the op-amp are both getting 5V in the right spots. Tapping from the mixing resistors towards the bottom of the PCB gets nothing but the PSG again.

If I tap the YM3016's BUF, MP, or BC pins (13, 14, and 15) I can hear the YM2610 audio, though it is distorted. I can also hear the static serial data if I probe it, so the YM2610 is fine and communicating properly.

However, on the YM3016's pins 10 and 11 (analogue output) I hear absolutely nothing. Is the signal out of it weak and I should not expect to hear anything, or is this a sign of a dead YM3016?

I pulled the quad op-amp off the board. If I tap into where the inputs for amp #3 and #4 went, I hear a similar distorted but definitely correct FM track. Maybe the op-amp is dead?

I still hear nothing out of the YM3016's output pins, though.

I've ordered a replacement YM3016D and C844 op-amp, as a precaution.

I socketed the YM3016D and installed the new one. Verified the old one's outputs were dead.

I replaced the Op-Amp, and all is well now.

Solution was basically a full replacement of the DAC and amplification stage.