Thanks for the feedback.
I will be reposting in Tech Forum.
Yesterday I spent about 4 hrs with 3 different amps, including the SF1, doing various outlet configurations.
Again SF1 was most "resistant" to any inpact from being plugged into different outlets or different conditioners, but I was also able to eliminate the problem with other amps (which I have been experiencing up to this point) by plugging it into a different outlet and also pluggin my pre-amp into yet another outlet...