Audio problem in Premiere Pro CS4

[Nikaido]

I was using Adobe Premiere CS4 4.0 and when ever I tried to add a certain song to the audio track some parts of the song will dip down for several milliseconds and then it goes back up . I tried normalizing the audio but it still continued to do it. So, I updated to CS4 (4.2.1) seeing if that was the problem. Nope, still did it. Tried re-ripping the Track from the CD into a WAV instead of a MP3 (320kbps). Still did it with the WAV file. Then I tried updating my audio driver, but come to find out it's already up-to-date. Thought maybe it was my speakers, but I still experienced it when using my headphones. I've also compared the Premiere waveform to Audacity's & Soundbooth's and saw no inconsistencies. Although I am experiencing the same thing in Soundbooth, but not Audacity.

I don't experience this drop in sound when listening to the files in Media Player, so...

Any help would be appreciated.