I think you may have misunderstood.
The ADC->DAC loopback operation works like this:
ADC samples X samples into buffer at whatever sampling rate ->
DAC converts these samples and plays out at pin
The A/D conversion and the D/A conversion both take time because, in my implementation, one occurs first THEN the second occurs (they aren't both loading and unloading the buffer simultaneously).
As such, there is a delay, however minute, between the instant the signal is sampled and then played back.
My question is... how long can that delay be? I'd like to sneak some additional calculating in between the conversions but, obviously, don't want to sacrifice audio quality/continuity for it.