Alternator whine after years of clean/clear stereo sounds

Dreaded alternator whine help!!
System:
-Pioneer AVH3200 dvd headunit
-mb quart 4.125 onyx amp
-ctx65 id front component spkrs & tweeters with crossovers mounted in kick panels
-id10" dual 2ohm sub

My system was rocking since self install back in 2011. I installed the transfer case 2 lo module I bougt from a member here and since then I've acquired the irritating alternator whine in my system. I also found I had a loose ground on my amp - i did not use a ferule on my 4 guage ground wire at the amp connection and wire had worked loose from screw clamp connection. I put ferules on and checked my amp connections (0.2 ohm on the amp ground as this is the lowest my multimeter goes down to) so all is good. I also removed the "2 lo module" and the whine is still there. So I did trouble shooting as follows:

-Engine whine still there with A/C on and off. Radio, cd player, etc..
-Whine still present with antenna and backup camera Un-plugged.
-No whine when RCA are un-plugged from Amp and still plugged to headunit
-No whine when RCA unplugged from Headunit and plugged into amp.
-Head unit grounds to bare metal chassis (not factory harness ground). Also have a ground connected to back case of headunit.
- Ground Loop isolator made whine worse (connected from back of headunit)
-Used inline noise suppressor (pac css12) on 12v ignition power wire to headunit and no change in sound. (Haven't tried it on the orange constant 12v lead)
-My 4 gauge power cable is NOT running next to RCA or speaker wires.
-RCA jacks are shielded knuconcept and run down the middle of transmission hump.

So I'm positive the sound is coming from headunit so I figured it must be the PICO fuse in my pioneer so I buy another pioneer avh201ex dvd unit and the whine is still there.
My alternator is putting out proper voltage according to my scanguage, however I did replace it with a NAPA gold remanufactured one about 3 yrs ago. Battery connection are clean and tight. Should I try the inline noise suppresor on the constant 12v lead to the headunit? Any other ideas?
Happy Thanksgiving TW!!

 

Odds are pretty good that something you did during that module install made this happen. I'd be focusing there. 99.9% of the time this is a ground issue. Were some grounds moved around then?

 

The "2 lo module" itself was plug n play into the factory harness and I installed it with battery disconnected and did not move or touch any other wires for install. Since I still had the whine when I removed the module I did reinstall it and my 4hi, 4 lo, and 2 lo all work so nothing fried in my 4x4 system as I can tell. I only moved grounds after the engine whine, i removed the headunit harness ground and ran it straight to chassis and added the extra ground to back of headunit case.

 

But the onset of the noise coincided exactly with that mod, yeah?

 

True, I’m going back in to check everything right now. Wish me luck

 

Oh, I am - noise is MADDENING!!!

Good luck!