Flash Video problems

[freak22]

I recently loaded a fresh copy of windows xp Pro SP2 on my system. I have basically loaded all software that was on the last machine however now I can not hear any audio when playing flash files. Example, if I go to espn.com a video loads in the right corner and begins to play. If i click on the settings in the video it shows an EQ with audio going up and down as to say audio is playing. The video plays fine however I can not hear it. I can watch MPEG, MP3, AVI, ect. I have load a couple of codecs to see if that would help but still cant hear. I also have uninstalled and reinstalled the Flash plug-in. Below is the specs of my computer. The audio software/drivers that come with the mobo is Realtek AC97 Audio. If anyone knows of a fix please let me know.


DFI LANPARTY UT NF4 SLI-DR nForce4 SLI Athlon 64(FX)/Sempron Skt939 DDR ATX Motherboard w/Audio, Dual Gigabit LAN, RAID/Serial ATA.

AMD Athlon 64 X2 4600+ Manchester 2.4GHz Socket 939 Dual-Core Processor Model ADA4600BVBOX

G.SKILL 2GB (2 x 1GB) 184-Pin DDR SDRAM DDR 500 (PC 4000) Dual Channel Kit Desktop Memory Model F1-4000USU2-2GBHZ

Antec TruePower 2.0 TrueControl II 550W Power.



Thanks
Jeremy