Basically because it's too expensive
and apparently the on-board sound card that PCS have is very good anyway, so I'm just sticking with that. That also supports 5.1, and if I get enough money in the future, I'll buy a 5.1 speaker system. I'll mostly be using the speakers for music anyway (a load of bass for my dubstep) and I'll be using my headset for games.
I changed the spec a bit more, and here's the new one:
COOLERMASTER CM STORM ENFORCER - GAMING ENTHUSIAST CASE
Intel Core i5-2500 Quad Core (3.30GHz, 8MB Cache) + HD Graphics
ASUS P8Z68-V LX: USB 3.0, SATA 6GBs, ATICrossFireX
8GB SAMSUNG DUAL-DDR3 1333MHz (2 X 4GB)
2GB NVIDIA GEFORCE GTX 560 - 2 DVI,HDMI,VGA - 3D Vision Ready
2TB WD CAVIAR BLACK WD2002FAEX, SATA 6 Gb/s, 64MB CACHE (7200rpm)
24x DUAL LAYER DVD WRITER +-R/+-RW/RAM
INTERNAL 52 IN 1 CARD READER (XD, MS, CF, SD, etc) + 1 x USB 2.0 PORT
CORSAIR 650W ENTHUSIAST SERIES™ TX650 V2-80 PLUS® BRONZE
SUPER QUIET 22dBA TRIPLE COPPER HEATPIPE INTEL CPU COOLER
ONBOARD 6 CHANNEL (5.1) HIGH DEF AUDIO (AS STANDARD)
GIGABIT LAN & WIRELESS 802.11N 300Mbps PCI-E CARD
6 x USB 2.0 PORTS @ BACK PANEL (MIN 2 FRONT PORTS)
Genuine Windows 7 Home Premium 64 Bit - inc DVD & Licence
22" Widescreen TFT 1920 x 1080 2MS, D-Sub, DVI, 21.6" Panel
22" Widescreen TFT 1920 x 1080 2MS, D-Sub, DVI, 21.6" Panel
2 x 2 METRE DVI-D CABLE
LOGITECH K200 USB MEDIA KEYBOARD
LOGITECH OPTICAL USB MOUSE
LOGITECH Z323 2.1 SPEAKERS - 30W RMS with 360 Degree Sound
6 Socket Compact 2M UFO Surge Protector
£1,211.00 or £37.02 p/m
Not a huge change, but it knocked a bit of the price, and I have a better power supply, just in-case I want to add more to it in the future, and ends up requiring more power.