pactl: 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/pactl - from package: pulseaudio-utils

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

On Debian possible default full paths are:

/usr/bin/pactl - from package: pulseaudio-utils

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

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