MP3

Join files

In order to merge multiple mp3 files into one, use mp3wrap. Backup at GitHub

mp3wrap <outputfile> <input1> <input2>

Add cover to file

Source

There are several tools (like eye3d):

lame --ti /path/to/image.jpg -b 192 /path/to/audiofile.mp3

mp3 to wave

Source

lame --decode file.mp3 output.wav

Fixing errors

Mp3Eval is quite the tool to analyse and fix mp3 files.

cp Makefile.linux Makefile
make
mp3eval ...