jack-dssi-host: command not found

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/jack-dssi-host - from package: dssi-host-jack

You may install the required package with command apt-get install {package}

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