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</o:shapelayout></xml><![endif]--></head><body lang=ZH-CN link=blue vlink=purple style='text-justify-trim:punctuation'><div class=WordSection1><p class=MsoNormal><span lang=EN-US>Dear all:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>I am dealing with a problem with USB earphone device. On my PC, I had two devices: A USB earphone and a regular earphone. The USB earphone worked. When I plugged out the USB earphone, the sound should switch to the regular earphone. So I called the function before restarting a new pipe:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>gst_element_set_state (p->playback.pipe, GST_STATE_NULL);<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>gst_object_unref (GST_OBJECT(p->playback.pipe));<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>However, the gst_element_set_state function blocked.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Now I am so confused and need your help.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Thanks!<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>--<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Yongjian<o:p></o:p></span></p></div></body></html>