LIN+ and RIN+ Pin outs shorted?

#1

I've just soldered a 40 pin header to my core, and when I did a continuity check I noticed that RIN+ and LIN+ appear to be shorted together. It's not a solder link because the pins are not next to each other. Is this to be expected.
Thanks for your help

#2

Yes, this is to be expected. The line-in signals are AC coupled to LIN-/RIN-, while the line-in jack ground is AC coupled to both LIN+ and RIN+. If you want to feed a balanced signal into the ADC from your own circuitry, you need to cut a few traces on the circuit board, LIN+/RIN+ are joined at C46.
This picture shows the highlighted LIN+/RIN+ net:

image.png1156x877 47 KB

#3

Thanks for explained not this. I suppose that I was expecting the common ground to be labelled - rather than +, and that's why I was a little confused