... what is Settling Time in cables and interconnects...

Here’s my take on the OP’s question.

Settling-in would generally mean that a broken-in cable needs a brief period in an audio system to settle-in before sounding optimal.
If a cable has not had signal for a long period of time it may need a longer time to either, 1. break-in again or 2. settle-in.
Some define break-in and settling-in as the same thing although generally break-in would take a longer period of time.
Some reject the whole notion as ludicrous. Thus the collective groaning when this thread was posted.
As a newbie I see no problem in asking the question but be warned, the answers can be contentious and divisive (and occasionally vitriolic) so the wiser here tend to avoid the discussion altogether. Of course there are always those who are itching for a fight.
Hope this helps.

1. I never suggested anyone should worry about it.
2. I was merely attempting to provide a definition for the terms.
3. I think we should all listen to gosta if we have any audio concerns.
Could it be that many of us are listening through signal cables that are not adequately burned-in?
Perhaps a device like the Audiodharma could change some opinions.

100 years from now probably nothing will matter to any of us so what’s your point? This is here and now.

No, you don’t have to be an audiophile to participate here but some experience/knowledge would be helpful don’tcha think?

Please always remember: Burn-in is better than burn-out.