Couple modifications are required for proper output levels.
1) on PCB1 cut the trace
2) wire the pin on a header that was connected to a cut trace to a right pin of R38.
3) wire left pin to a ground thru 2K2 resistor
4) on PCB2 cut the race between pins 1&2 of IC8
5) solder 0603 11K resistor between these pins
6) solder 10K resistor from pin2 to a ground.
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