Z170 audio issues

Serious buzzing happens when running any game on my pc, even after installing a pcie sound card. I have changed drivers, and updated the bios and even added a sound card. The audio is perfectly fine for anything until i play a game, so can anyone tell me if i need to replace motherboard or try something different.

PC specs:
Gigabyte z170 HD3P
Intel i5 6600k
Gigabyte GTX 970
Viper 4 RAM x16GB
Creative Audigy SB 5.1

Thank you.

Headphones or speakers?
If headphones, can you hear it without wearing the headphones?
Are you using the rear IO jack or the jack on the front of the case?
Does switching between front and rear jacks change anything?
Can you hear it with no audio playing at all?

Power supply?

“Audio Noise Guard with LED Trace Path Lighting”

looks like the on-board audio has isolation circuitry, only happens when playing a game so your graphics card is drawing more power which could be causing crossover noise from the power supply.

maybe try the audio out from the GTX 970 to HDMI on a TV?