Helix HXA40 driver card issue

I rebuilt channels C and D of this amp only to find the driver card for channel C has a trace problem. I replaced 3x MPSA42 and 2x MPSA92 on the driver card to no avail. All SMD components are measuring correctly while in circuit. I re-soldered all the components a few times but still cant get the driver card to operate correctly. I moved this driver card to another channel and its definitely the card thats the issue. There are not too many components on the card but I cant figure it out. Any channel will go to -26vDC with this driver card.

Any clues or a schematic? Has anyone seen one of these amps? Im almost wanting to just replace the driver card at this point but dont know where to source parts.

It looks easy, but its been kicking my behind even after checking whatever I could compare for about an hour with a working card.

Pic of the card


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I've done few of these. Oddly sometimes the LED go bad. Check the LED if they are fine. I've had a few cases where a bad LED would give a DC at the speaker output terminal or make the amplifier go into protect. I could not find schematics nor where to source a new driver board. Contacting manufacturer would only get me a "bring it in a authorized service center of us".