Disable the Power Management feature of the Realtek sound, that does wonders for me
launch Reg Edit, then navigate to:
HKEY_CURRENT_USER\Software\Realtek\RAVCpl64\PowerMgntNow Double click on
Enabled and set the value to 0 then reboot
ALIENWARE 18 LaptopCPU: Intel Core i7-4900MQ CPU @ 3.8 GHz (8MB Cache)
Graphics: Dual GeForce GTX 780M SLI 2x4 GB GDDR5 RAM
Sound: Realtek ALC668 HD Audio with Klipsch Speakers
Memory: 32 GB Kingston HyperX 1866 MHz DDR3 PC3-14900 RAM
Storage: Samsung 850 PRO 256 GB SSD + Samsung 850 PRO 1 TB SSD + Samsung 840 EVO 1 TB mSATA SSD
Screen: Samsung LTM184HL01 18.4" WLED FHD (1920 X 1080) TrueLife Display PLS 16:9 1080p [SDC4C48]
OS: Windows 8.1 (x64)