the audio codec for your file is not installed/supported by adobe premiere. i've had that happen multiple times, i had to re-encode the video into raw avi before i could properly import it into premiere. it sucks, i know, but if anyone knows how to actually fix this problem rather then avoid it, please post!
This is so messed up, this worked a couple of months ago, and I was still using K-Lite Codec Pack, is there another Video Editor that anyone can reccoment that is compatible with Vista, i tryed Pinnacle, but it wasnt supported by Vista