intermittent buzz when gaming

Recently my system has started to omit a buzzing sound from my speakers. It only happens or I only seem to notice it when gaming (wow, borderlands 2, etc). I've tried to reproduce it during an MSI benchmark test using MSI Kombustor 2.5 with sound but i can't reproduce it unless I'm in a game.

 

The 'buzz' sounds like if your speaker cable was not plugged in correctly or if you touch metal. My games won't lock up, or the computer does not freeze but I do think it will jitter ever so briefly.

 

I'm using the motherboards sound card at the moment. This issue happends if I'm using headphones or if I use my computer speakers.

 

This is a new system (about a month old) and I haven't really made any changes when this started to happen other than testing out some overclock settings, nothing very aggressive at all, all within safe-zone specks.

 

Any idea? PSU? MB? VID? My system info is below. My next step in troubleshooting will be to disable the MO sound and use the vid cards sound.

 

Some have said its probably coil noise coming from your graphics card. Happens on some cards when load is high or FPS is high. i.e.

But my issues is not an ongoing buzz like in this youtube. mine is a quick "bzzt" and then it stops.

 

also, I set my games and config for the card itself to ON for vsync and its still bzzt'ing.

 

And THANKS for the help

 

CPU: Intel Core i5-3570K 3.4GHz (x47)

CPU Cooler: Corsair H100i Liquid CPU Cooler

Motherboard: MSI Z77A-GD65 ATX LGA1155

Memory: Corsair Vengeance 16GB (2 x 8GB) DDR3-1866

Storage: [OS drive] Crucial M4 256GB 2.5" Solid State

Storage: [RAID 0] WD VelociRaptor 500GB 3.5" 10k RPM

Storage: [RAID 0] WD VelociRaptor 500GB 3.5" 10k RPM

Storage: [back-up] Toshiba 2TB 3.5" 7200RPM Internal

Video Card: Galaxy GeForce GTX 670 2GB

Case: Corsair 650D ATX Mid Tower

Power Supply: Corsair Pro 850W 80 PLUS Gold Certified

Optical Drive: LG UH12NS29 Blu-Ray, DVD/CD Writer

Monitor: Asus VH236H 23.0"

OS: Win7 Pro

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