Hey Nanang, Thanks for your reply. I don't really know to describe this problem clearly. But what I get is a lot of NOISE, I hear TICKS, and a half duplex call. And BTW, does VAD have something to do with this? and if yes, how can I disable it? -- a. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/attachments/20080521/935c43f4/attachment.html