To contact / merge multiple mp3 files I use sox
command line tool
For mp3 suppoet I installed libsox-fmt-mp3
$ sudo apt-get update -y
$ sudo apt-get install -y sox
$ sudo apt-get install libsox-fmt-mp3
$ sox 1.mp3 2.mp3 3.mp3 out.mp3
To contact / merge multiple mp3 files I use sox
command line tool
For mp3 suppoet I installed libsox-fmt-mp3
$ sudo apt-get update -y
$ sudo apt-get install -y sox
$ sudo apt-get install libsox-fmt-mp3
$ sox 1.mp3 2.mp3 3.mp3 out.mp3