Still some stereo noise.

Hey guys.
I'm still experiencing alot of noise coming into my amps from the alternator and various other devices. Specifically when the engine is on. I now noticed that whenever i have the ventilation system to high, the speakers immitate the sound that the vent motor is making. Engine whirr is also heard through the speaker. I grounded the ground loop isolator wire on my rca's, as well as re-did all grounds under the hood and to my amps with 4 gauge. All paint was stripped and ground down to bare metal, including the bolt. A new 4 gauge wire was ran from the alternator housing to the battery also.
I'm running out of options here. I reduced the noise tremendously, but it still exists. It's getting on my nerves.
And yes, the wires were ran on the opposite sides of the car.
Thanks guys
-Ross