Come over to the Audio Video Improvement and Special Guest forum here at AV Science, and do a search for both "cheater" and "ground loop" and you'll see quite a bit of information in the past six months on this. And that fact that though cheater plugs may work, they are a safety hazard which even I the incessant tweaker can never recommend for reasons of safety alone. Better to find out why your system hums and eliminate the hum using a safe practice!
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Steve Bruzonsky
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Steve Bruzonsky