More info;

Outlaw 7700 amp, 3 prong plug
Marantz 7005 preamp, 2 prong plug
Panasonic Plasma HDTV, 3 prong plug

I wired a 14 guage wire from the preamp (ground scew) to the amp (screw on top front) to insure a ground. I tried running that wire right to a water pipe, and even though the DirecTv line is grounded right after it enters the house and prior to it feeding a 4x8 mulitiswitch, I grounded it again onto a water pipe above the stereo cabinet.

None of this helped.
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Panasonic TC-P65S1 65" Plasma HDTV, Marantz AV 8801 Preamp, Outlaw 7700 Amp, Klipsch RF7 (X-over dean G modded) RC7 (X-over Dean G modded) RS7 CDT-5800C speakers, Outlaw LFM1 EX Subwoofer, Oppo BDP-93, B & O Turntable, Toshiba HD-A2, Sony CD & DVD 400 disc jukeboxes, DirecTV HD-DVR, PS2, PS3, Wii, Harmony one remote, Monster PowerBar 1200 for the TV, sub, PS3, HD DVD and Wii, Tripp Lite Isolation Bar for the Amp, Pre-Amp and other sources.