I had a 600fps, camera tracked clip and tried importing a song over it but the song would not playback properly, so i changed the comp framerate too 59.94 and the 600fps, camera tracked footage was v ery choppy, anyways Ive decided to scrap it and restart completey. I think the best thing to do now is go to interpret footage in the project panel and change the framerate to 59.94 before importing the clip into the timeline.
Strange that the audio playback would not playback correctly though when the project was set to 600fps. I also imported the project from premiere pro into ae, just because i find it easier to cut the clips up in premiere than Ae.