I was examining the PCM2704 datasheet to compare their suggested circuit to what was included in a simple DAC I have when I noticed some differences. Specifically, on my DAC there are no pull-down resistors on the output (in front and behind the caps). Are these something that I should add?
Also, I was wondering about series resistors on the headphone output. I noticed that some people add 120 ohm guys in series at that location. What are the benefits/uses of this? It's gonna increase the total output impedance, and I would guess it will cut down on volume and lower the noise level.