This is a normal function of the Copy feature; the new file will have the same sample rate and file type as the session itself.If for some reason it is required that the audio file remain at is original sample rate or type, simply use the "Add" function instead of the "Copy" function. This will cause the session to access the original file for playback, not making a new copy. (The only option will be "Convert" if the file type or bit-depth is unusable by Pro Tools.)