I cannot walk, simple enough. I start up the game and find out I cannot walk, I can turn by pressing the walk buttons but my character refuses to move. I can jump and move in mid air and then it lets me walk for a few seconds but then suddenly stops and starts turning around on place again. Also, I can crawl and move.

My specs are:
Intel i7-3770K 3.5GHz, 8MB
Intel Z77
NVIDIA GeForce GTX 670 2GB GDDR5
Kingston HyperX 2x4GB, DDR3 1600MHz, CL9
Western Digital 1TB Caviar Green, 3.5", Sata3, IntelliPower, 64MB
Asus DRW-24B5ST