fishsound-encdec: 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/fishsound-encdec - from package: libfishsound-tools

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

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