"I turned off the preamp with amps on and the buzz came back but this time the buzz was much quieter and no sub hum this time around, I unhooked the active shield of the cable and the buzz went away"
Just from what you said, it would appear that something about the "active shield" is causing the problem. I'm assuming that you told Synergistic about your finding. I'm curious about what Synergistic had to say.
Another thing you might want to try, is take the sub off the "house circuit" and try it on your "dedicated circuit" and see what happens. I'm thinking that because you amp is on a "dedicated circuit" and that sub is on the "house circuit", that the sub cable (or active shield) may be acting like an antenna and picking the "buzzing" noise.
Just from what you said, it would appear that something about the "active shield" is causing the problem. I'm assuming that you told Synergistic about your finding. I'm curious about what Synergistic had to say.
Another thing you might want to try, is take the sub off the "house circuit" and try it on your "dedicated circuit" and see what happens. I'm thinking that because you amp is on a "dedicated circuit" and that sub is on the "house circuit", that the sub cable (or active shield) may be acting like an antenna and picking the "buzzing" noise.