Ground Hum & Ground Loop Isolators

[rarredoa]

I get a very loud room-shaking hum that remains on whenever I shut-off my receiver. The hum is coming from the low-frequency drivers of my Polk Rti12's which are bi-amped by an external professional amp. The amplifier's signal path is complex. The signal originates from the receiver's speaker level outputs, converted via speaker-to-rca circuit converter, and finally level-matched to XLR (the receiver does NOT have rca pre-outs). The high frequency array is powered by the receiver's on-board amps.

I realize that all thse signal paths and conversions are just begging for ground-loop noise. All these sources, except for my computer, are all plugged in to an APC Surge Protector. Powering the computer from the same APC outlet is not an option.

The sound coming from audio sources is, quite frankly, the best i've heard, until I power the receiver off... at which point, the hum is exaggertingly loud.

Will one of these ground-loop isolators solve this?