I have a fair number of mp3 files which I created using audiohijack pro on a mac. Now I no longer have a mac and am using them on my linux systems. Unfortunately the program I use (rhythmbox) to listen to these files cannot figure out how long the files are. These files are up to 5 hours long, and when the program cannot figure out how long it is I can't scroll through the file. Any unix/linux programs that can reencode these files? I do not know enough about either audio on linux or the mp3 file format to know what would be involved in this.