[Dozer]

To break in an interconnect, can you run the source, but have the preamp or integrated amp actually tuned to another source?   Or does the source have to be playing through the speakers for the break-in to occur?

I just want to be able to break in a cable while watching TV using the same rig...    Doable, or is it counterproductive?  

Yes I don't believe in expensive cables or breakin, but I bought some anyway so I might as well break them in right....    

Thanks.

[Malcolm Fear]

Let's assume you interconnects are from cd player to amp.
I would think that the pre amp would have to be turned on, with the input selector set to cd, with a cd playing on repeat, with the volume (or power amp) turned to zero. I do this when I go to bed, when I wish to break in an interconnect.