atsa: 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/atsa - from package: csound-utils

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