No RTCP sent on hold


I have a problem in my Call-Center.

The caller is not receiving any RTCP when the agent is on hold. Without RTCP some clients hang up.

This is the scenario:

  • SIP Call enters Asterisk
  • Asterisk answers the call
  • Caller hears ringing (RTP+RTCP from Asterisk)
  • Call enters Queue
  • Agent answers
  • Agent puts call on hold (sendonly)
  • Music starts, call is redirected through Asterisk
  • Caller hears music (only RTP, no RTCP)

These are the traces with SIP traffic on placing the call on hold:

I would appreciate any idea to force the RTCP transmission.