If you want to break it in, why not just play music. Seems to take awhile even if I am just plugging and unplugging interconnects, cords, speaker cables it takes awhile for everything to get back to the same sound but it's not that dramatic.
What use to burn in power cords?
Is there a small electronic device or a burn in device that I can leave on 24/7 to burn in my 15A IEC power cords?
What do you use?