playbin does not smoothly in first 30 seconds when play MP3 audio

[Soho Soho123]

Hi all,

when I use the pipe below:
gst-launch-0.10 playbin2 uri=pushfile:///var/tmp/usb/sda1/audio_src/test1.mp3
I got the result:
the first 30 seconds, the sound is intermittently.
and then the sound is more smoothly.
Does anyone have idea about this phenomenon ?

it seems alsa device does not have enough data to playback, right?

Any input is appreciated!

Thanks!

Best Regards,
Soho