title: Cannot send RTP by SIPp tool
body: <p>I am trying to replay an captured pcap file with sipp as follows:</p>
  
  <p>In Sending.xml</p>
  
  <p>...</p>
  
  <pre><code>&lt;recv response="200" rrs="true"&gt;
  &lt;action&gt;
  &lt;ereg regexp="(.*)" search_in="hdr" header="To:" assign_to="TO_REQUEST"/&gt;
  &lt;/action&gt;
  &lt;/recv&gt;
  
  &lt;send &gt;
  &lt;![CDATA[
  ACK [next_url] SIP/2.0
  To: [$TO_REQUEST]
  From: [$FROM_REQUEST]
  Via: SIP/2.0/[transport] [local_ip]:[local_port];branch=[branch]
  Call-ID: [call_id]
  CSeq: [last_cseq_number] ACK
  Contact: &lt;sip:[local_ip]:[local_port]&gt; 
  [routes]
  Max-Forwards: 70
  Subject: Performance Test
  Content-Length: 0
  ]]&gt;
  &lt;/send&gt;
  
  &lt;nop&gt;
  &lt;action&gt;
  &lt;exec play_pcap_audio="pcap/g711a.pcap"/&gt;
  &lt;/action&gt;
  &lt;/nop&gt;
  </code></pre>
  
  <p>...</p>
  
  <p>However, I always get the same error:
  extract_rtp_remote_addr: no IP address found in SDP message body.</p>
  
  <p>I tried to test with other *.pcap and *.raw files and edit my script but I still cannot.
  When I only send the signal not RTP, the call is successful.</p>
  
  <p>Anyone can help me send RTP by SIPp?
  Thanks in advance! </p>