crackling sound. tried everything. PLEASE HELP!!??

I get cracking sound whenever I play a game or when a movie gets loud for example maybe a fast driving scene and then a wreck I get crackling sounds and pops. I get them when I load up nintendo roms and also new games like far cry 3. I get it when windows media center is loading up. It is very annoying. I've tried different games and video all the same. I have it set up using HDMI from my video card to my surround sound then to my tv. I am running Windows 7 64bit and so far this is what I have done to try and fix it.

-bypassed surround sound (directly to tv)
-bypassed HDMI and used the 3.5mm output directly to tv
-tried updating and even rolling back to every driver I could find for realtek or nivdia, also ATI when I switched video cards
-tried each device individually after uninstalling the other and removing drivers.
-Moved video card to different PCI slot (PCI 3.0)
-replaced motherboard (rma'd and got a new one)
-replaced video card (rma'd it and tried different brand)
-disabled onboard sound in bios and windows (used only video card sound)
-installed sound card (disabled all other sound devices)
-installed windows multiple times (fresh install, no driver except video card, then the same with no driver except onboard audio)
-disconnected all headers from the motherboard (usb, panel audio, etc...)
-disabled usb devices in bios
-set memory frequency down from 1866 to 1600 and then 1333
-downloaded DPC latency checker but im not real sure what to do with it. I can see it is in green then partially yellow then almost on schedule every few seconds it spikes into the red then back down over and over again. I don't exactly know what this means or how to use this program.


I do not know what to do. Can anyone please help?

My specs are below:

Asus sabertooth 990fx GEN 3 motherboard
AMD FX-6300 6core CPU
Currently - MSI NVIDIA 660ti/PE-OC (also tried Sapphire HD7950 Vapor X)
8GB (2x4) G Skill Memmory @ 1866
NZXT Phantom 630 Case
Windows 7 64Bit