Don't you still have that ATS-909 portable to take and noise hunt with that? I had to do that with that Eton pussy E-10 portable that I had. Two years ago I track down that my UPS was a colprit in on / off noise that pulsed. I've reduced that, but not eliminated it. And down in the basement I've tracked down to a surge suppressor, where I suspect that I've got some bad MOV's in it. But, you are right about cheap switching power supplies that they put in just about everything now a days. Damn, I miss transformers. Oh, and the new 120VAC LED light bulbs have real schytty switching PS's in them as well. That, and about every USB plug charger that plugs into 120VAC. Yep, either ferrite, or capacitor bridge, the hell outta' that stuff.