Help in Adobe Premiere Pro CS3

Hi All,
I am facing a problem in editting AVI file in Adobe Premiere Pro CS3.
when importing the file it start playing good but after about 2 minutes a certain part of the audio is looping tell the end of file while the video is working good.
Also note that the file is working good in Media Player.
I have the following in my System:
Windows 7 Professional 64X
K-Lite Mega Codec.
K-Lite for 64X

I really need you help I am trying to edit this file since 22-8-09

Thanks

would you please any one help me