It doesn´t matter if it is UDP or TCP since it is not a digital problem. The packages has been showed to always arrive perfectly in a normal home/hifi situation: https://www.alpha-audio.net/background/measuring-ethernet-cables-part-1/

To summarize this thread (feel free to object) this is mainly a noise problem in the digital domain that causes the square waves (electrical pulses that forms the bits) to become irregularly shaped in the DAC step. The human brain is very sensitive to the time domain and can notion when the time:ing is off (caused by these irregularly shaped square waves) down to pico seconds, from what i understand.

We are mainly talking about measures to make sure that these square waves (bits) are as accurately shaped as possible, by mainly removing as much noise as possible, before the DAC step.

These are theories explained by Hans Beekhuyzen recently.

No problem 😉

Indeed just as Tobias already mentioned it is not a digital problem. It is an analog problem. Digital signals are interpreted out of the analog. So the better the shapes of the square waves, not even knowing what the best shape will be. Still I'm pretty sure they must be smooth in some way.

Personally I think the time domain is just a factor, maybe not even a very big one. I think noise in general is causing several effects.