buzzing in the speakers, speaker shields

ok, before reading my question, reference a picture of my 03 GT's audio wiring schematic, which i took a screen shot of and is located [url=https://i119.photobucket.com/albums/o151/IRSmart2004/untitled-29.png]here[/url].done? perfect. ok, on the right side of the screen you see the radio, with 3 wiring harnesses plugged into it. the one on the top is for the front and rear amps. the one on the bottom is for the speed sensitivity that the stock mach 460 has. the one in the middle is for everything else.i installed a JVC touchscreen radio a few days ago and i have 2 questions, that may be related to each other. i'm not sure, so here goeswhat are "speaker sheilds"? per the wiring schematic, in the top wiring harness there are 2 wires, one in pin 3 and one in pin 7, that are for the front and rear speaker shields. i didn't wire the aftermarket wiring harness up to anything on the radio because i wasn't sure what to do with them. the "AMP TURNON" wire goes to the "HIGH AUDIO MUTE" and "LOW AUDIO MUTE" located in pins 4 and 8 so that the front and rear amps turnon. i didn't hook a test light up to the speaker shield wires so i don't know if they just turn on when the radio comes on or not, in which case the amp turnon wire should feed the speaker shield wires too, right? or should i just leave those 2 wires alone, like i did?my second question is regarding a buzzing sound. it is coming out of the front and rear amped speakers, which are fed by the amp out RCA plugs in the back of the aftermarket radio, into the Metra wiring harness, and then through the factory amps. the buzzing gets higher in pitch as the car goes faster. i tested it, it's not as the RPMs go up, it's speed related. now, the third wiring harness that has to do with the speed sensor is not plugged into anything, it is just dangling behind the dashboard. any idea's what could be causing the buzzing sound?and i got to thinking (dangerous, right??). since i don't have the front and rear speaker shields hooked up to anything, could these be related? if i do something with the shields, will it stop whatever buzzing sound i'm hearing?sorry about the long post, but if anyone that can help me out i'd appriciate it. thanks!!

Did you use a  Metra Electronics Corp. - 70-5519  amplifier integration harness?

anyone have any idea about these speaker sheilds?