soxi: 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 CentOS possible default full paths are:

/usr/bin/soxi - from package: sox

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/soxi - from package: sox

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

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