On Jun 28, 2018, at 3:37 AM, Melek Oktay <melekoktay@gmail.com> wrote:

Hi,

I realize very interesting problem of my software stack (FreeSwitch + Kamailio)  with  Yealink 41P Voip phone.. 

After 3-4 days research, I realize Yealink phone does not try to start RTP session if it gets UPDATE packet before ACK packet !! 

In Freeswitch side, do we have a option that send UPDATE packet after RTP session is established? (we have a option in FreeSwitch side: do not send UPDATE packet  however this is not good case for me, I update CallerID  with this UPDATE packet)