faust2dssi: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/faust2dssi - from package: faust

You may install the required package with command apt-get install {package}
Error in other languages:
faust2dssi: bevel nie gevind nie
faust2dssi: comandă negăsită
faust2dssi: comando não encontrado
faust2dssi: commande introuvable
faust2dssi: command not found
faust2dssi: käsku ei ole
faust2dssi: không tìm thấy lệnh
faust2dssi: komanda nerasta
faust2dssi: Kommando nicht gefunden.
faust2dssi: kommandot finns inte
faust2dssi: komut yok
faust2dssi: nie znaleziono polecenia
faust2dssi: níor aimsíodh an t-ordú
faust2dssi: no se encontró la orden
faust2dssi: no s'ha trobat l'ordre
faust2dssi: opdracht niet gevonden
faust2dssi: parancs nem található
faust2dssi: perintah tidak ditemukan
faust2dssi: príkaz nenájdený
faust2dssi: příkaz nenalezen
faust2dssi: команда не найдена
faust2dssi: командата не е открита
faust2dssi: 命令找不到
faust2dssi: コマンドが見つかりません