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Originally Posted by splaz  That doesn't make much sense, if the pad's weren't connected properly the resistant should be higher, not lower.
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Under normal operation, a current flows into Iadj through R31 to set the voltage. This means that there must be a path to ground through this pin. Measuring resistance in-circuit isn't always foolproof as there can be other paths for the measurement current to take. I can't tell for sure if that's what's happening, but it's definitely plausible. Also possible of course is that the IC is fried and you're measuring some effects of its failure.
If your voltage rails are sagging that badly when you plug it in it's almost certainly a short somewhere. This doesn't necessarily mean that two pins on the PCM2702 are shorted, but that's the most obvious conclusion to come to. I'd try to measure it out - use a DMM to test for continuity between all adjacent pins and compare to the datasheet (there are a few pins on the IC that are internally connected). It could also be away from the PCM2702, say a ferrite accidentally placed where a capacitor should be, or a short to the ground plane where the solder mask has been scraped off or something like that. That said, I had the same problem with my HPDAC build and wasn't able to track it down without first destroying the solder pads. Good luck
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