QSound embedded imx6 ubuntu running error: using null output device, none available

[maatong]

Hi all:
I'm a beginner of Qt, now I'm working on a small program which can play wav files with QSound.
I tried to run the program on my PC which runs ubuntu 12.04, it worked.
But when I tried to run it on the ARM system, there's a error notice read that:

using null output device none available.

So could anyone help me with that error?
I've installed gstreamer, but it still doesn't work.
Is it because I missed some libs or other resources?

Thanks a lot.

The codes are here:
(It's a Qt console program)
audio.pro:
@QT += core

CONFIG +=qt thread
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets multimedia
 
QT -= gui
 
TARGET = audioconsole
# target.files=audioconsole
# target.path=/home/ubuntu/audioconsole
 
#INSTALLS == target
 
 
CONFIG += console
CONFIG -= app_bundle
 
TEMPLATE = app
 
 
SOURCES += main.cpp@

And the main.cpp file
@
#include <QCoreApplication>
#include <QSound>
#include <stdio.h>

QSound player("/home/ubuntu/audioconsole/affirmative.wav");
 
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
 
printf("audio test\n");
 
player.play();
 
printf("succeed\n");
 
return a.exec();
 
}

@

[maatong]

I found a website said that, on embedded linux, there should be a build-in sound mixer which can be directly accessed from /dev/dsp.
Currently my device doesn't have such a device, how can I map a device to that directory?
Thanks a lot.