Flashplayer videos will only play for 2 seconds

I been trying to fix this issue ,but no luck. I could only play 2 seconds of a flash video. my pc is P4 2.2g m512 and a 80HD. I format the pc because i got a virus and now i have a chopper sound on my speakers and blurry pc and the flash is not working. I do have the new flash player 9