Maddening HUMMMM

In an attempt to get rid of a very loud speaker hum from my tube monoblocks, I've done everything I can possilbly think of, including the following;
Changed out Interconnects, the pre amp, and the speaker cables and the speakers. I've pluged each amp into a Lightspeed A/C filter, and then gotten rid of the filter and plugged directly into the wall w/o the filter. I've plugged the amps, via a 10 gauge extension cord into different wall outlets, including one dedicated outlet. Cheater plugs, then no cheater plugs, then different combos of cheater plugs or not. I disconnected the pre and had just the speakers cables to the speakers. I tired a different speaker. I've gotten up at 4 AM and turned off each circuit at the panel, then listened again. I even tried a different amp. I've lifted the cables off the carpeted floor. Using tape and assorted other devices, I've made certain that now power cords are anywhere near the ICs or speaker cables. All Components are on rack with carpet piercing spikes. NOTHING I DO ELIMINATES THE HUM.

This all started about six weeks ago when I rearranged my room and hooked up my system on the other side of the room. No hums before. Now the mega hum. This is no small noise. This is loud enough to hear in the next room. HELP ME, PLEASE, OR PUT ME OUT OF MY MISERY!!!!! Thanks for any advice you might offer. I've tried everything I can think of. Kolledog