Sound quality of the built-in DAC…seems decent to me (from the 11th gen Batch 2). The power on / off pop is not something that I’ve noticed with my laptop (in combination with SRH1540, DT1350 [85.9 ohms], SE846 [11.0ohms], UM Pro 10)
Also, the noise floor is not something that I’ve noticed either. [Blind test with youtube silence video play / pause.]
That is, it’s a usable / passable DAC without much fuss.
There was a DAC change in the later batches, and I believe that’s when the on / off pop behaviour becomes audible. Not sure what DAC is shipped with 12th gen units these days.
With the HD560s, I’m guessing you’re not looking at a portable solution…so, if you WANT quality…external DACs is the way as always.