Tizen Developers

Hi everyone I run the sample MediaPlay app(Tizen IVI 3.0) on target device. It can find all the MP3 files.When i play the music ,Start playing music,but it does not have any sound. so i re-brush system on device and first time start the system,it is working fine. when i reboot system,the problem come again. I run the same app on emulator,There is no problem. could anyone know why,thank you very much. Note:I used audio tag to developed a web application, it have the same problem. Bray.