audacity, sample rate conversion changes speed

i'm having a bit of trouble converting an audio file with audacity. i'm working with a 14m chunk of audio that i recorded on the edirol 09 at 16/48. each time i try to change the sampling rate to 44.1, it stretches the file to 15m and then it plays slow. i've never experienced this problem before but i've never mastered with that bit rate and sampling rate combination before either. haven't found any info on the net about this. i tried upgrading to the latest stable version and the problem continues. hope someone here can help.

You have a setting wrong in Audacity. Even when the right settings are checked, Audacity will add a bit of silence on the end of the .wav, a real pain if you want to convert several 24/48 .wav's to CD quality without combining the tracks first and then re-tracking the whole show. This is a much better, higher quality, free sample rate converter, adds no silence, and will convert bit depths with dithering as well if you need that:
http://www.voxengo.com/product/r8brain/