ADC input range confusion

I'm trying to use the line level inputs of the WM8731 and the "Absolute Maximum Ratings" below was confusing to me:
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As can be seen, the datasheet says the absolute minimum for analog inputs are AGND(0) - 0.3V = -0.3V whereas a line level input could swing to -1V. I also see a lot of projects just using the line inputs on this chip disregarding -0.3V. I see on the datasheet and it definitely works. So the logical conclusion is that I'm missing some obvious knowledge. Could anybody explain?

Best
 
When you apply +/- 1.4 V to one side of the capacitor and connect the other side to the IC input pin, the IC ensures the DC voltage at its input pin becomes approximately 1.65 V. The momentary voltage at the IC pin then swings from 0.25 V to 3.05 V, which is well within the -0.3 V to 3.6 V rating. See the suggested application circuits in the datasheet.

Actually, the voltage can temporarily go negative at start up, when there is already signal at the input while the capacitor is not yet charged. ICs are usually designed to handle that as long as the current is not too large (preferably < 10 mA, definitely < 100 mA).
 
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-1.5V on any pin will destroy the chip, so they don't clearly can't put that in the absolute maximum ratings as it would be a lie. Absolute minimum/maximum voltage on a pin is exactly that, as this is a datasheet for the chip, not for a whole circuit/module using the chip.

Experience teaches you that this is a single-supply device (some devices generate a negative rail internally, but that would be obvious as there would be a pin for that rail to allow decoupling capacitor(s) on it). The Vmid pin is a giveaway that this devices is single supply.
 
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Very sorry to ask again. Just trying to wrap my head around it. So these pins are AC coupled, meaning that the voltage on these pins will swing around 0V (ground) as the capacitors will get rid of any DC bias, how is that not below the min rating of these pins (which are at max -0.3V). I do understand that the chip has an internal bias at Vcc/2 but it's not on the "pins" it's after, an internal stage no?