i tried that but it did not give an option to convert a 320mb mp3 to a 128
single file load file you want to convert
select file \ save copy as then select what file format you want for example mp3 then in new box in options choose bitrate freq etc etc then ok
if you have a load of file todo use batch processing, you can even save the settings as a batch name so the next time you just select the files and call the batch name.
shame on you saying audition cant do it