4 Pole Mission Debugging [SOLVED]

So I have a problem child, I just did 3 of these without incident but I have one that I cant sort out: All chips have been swapped out, all part values checked problem persists: No audio at all on the outputs, I can track the output to the 4051 but nothing comes out of it, there is no thump on power up. All voltages check out. I am sure it’s something obvious I am missing but any input would be appreciated…

If you are sure you didn’t swap the 4051 and 4053 have you checked your 595 is alive?

Yes and the LEDs light up when the resonance is cranked so I am assuming the 595 is fine (I swapped that as well just in case)

Check the digital inputs of the 4051 and 4053 with either a multimeter, scope or a low current led + resistor.
Sometimes the sockets cause problems. Measure directly from the pins of the chip.

thanks but i dont use sockets

> to the 4051 but nothing comes out of it

Where do you check?

IC2 pin 8?

It actually went way past that up to pin 7 of IC1 but I lost after the 68R resistor which is pretty odd so I checked continuity to ground and the output was in fact shorted. Busted out the stereo microscope and there it was, hairline manufacturing fault on the out pad of the 68R beneath the solder mask. Snipped that at all is good…