NiAudioSample: 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/NiAudioSample - from package: openni-examples

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

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