Than you jimates for your reply.
I am not saying there is a problem with my Obi110. Could be with Obion or Obi network.
You are right. Just after I answer the calls. I am sure there is no problem with my network. My asterisk works perfectly at the same time. I mean, my sister calls me from her Obion softphone and there is the problem; She calls me from a softphone using SIP an there is no problem at all.
If the problem were the network then the complete call should have problem and no just the first 10 seconds.