soundkonverter: 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/soundkonverter - from package: soundkonverter

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