jetter
I was assuming (please don't give the overused definition of assume) that if a component has power that it would be full power, all or nothing if you will. I never thought that cleaning the outlets and pc prongs could make a sonic difference.
dirty contacts produce micro-arcing. What is is form of noise. Since noise on any circuits in the house can migrate to the audio circuits, best to clean all contacts IMHO.
jetter
Does somone use a cleaner on them, or just unplug and then re-plug in the power cord a couple of times and the abrasion cleans the prongs?
clean prongs of all plugs including fridge, tv, computer, etc.