Maximum PC

I'm recording Crysis II with FRAPS 3.4.0. I maintain at least 25 FPS and average 35. However when i play it in Windows Media Player it lags so much that the video will freeze but sound keeps going.
My FRAPS settings are:
60 fps / Full-size
Loop buffer length: 30 sec
Record Win7sound on / Stereo on
Force lossless RGB capture on


SPECS:
HAF X case
22" LED LCD
Windows 7 64-bit
700W Coolermaster PSU
M4A785TD-M EVO Motherboard
8Gb RAM @ 1333
AMD Phenom II x4 965 BE @ 3.4GHz
ASUS HD6870 DirectCU 1Gb Factory overclocked @ 915/4200
HD1: 1TB Western
HD2: 1TB Seagate