I'm not trying to start a blood war; Just asking out of ignorance and curiosity:

We can assume that a properly healthy ethernet network corrects packet delivery issues, and delivers bit perfect data. Therefore, the only issue I can imagine at stake are timing issues (jitter), and given the huge attention high-quality digital audio companies now pay to minimize all forms of both internally generated and external jitter . . .

How can a router or switch make much difference?

We've seen counterintuitive things in audio turn out to be real in the past, so I'm not denying the possibility, but I can't imagine the mechanism. Any insight would be appreciated.

Thanks

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